They go against sharee’ah and use as an excuse the fact that there are righteous people who do that

Firstly: 

The fact that some of those who go against sharee’ah are
justifying what they do based on the actions of some imams of mosques or
some teachers of Islamic education, will not benefit them before their Lord,
because what is required of the Muslim is to follow the example of the
Prophet (peace and blessings of Allaah be upon him), and it is not
permissible for him to put the teaching of anyone else before the teachings
of the Prophet (peace and blessings of Allaah be upon him). Allaah says
(interpretation of the meaning): 

“Indeed in the Messenger of Allaah (Muhammad
صلى الله عليه وسلم) you have a good
example to follow for him who hopes for (the Meeting with) Allaah and the
Last Day, and remembers Allaah much”

[al-Ahzaab 33:21] 

“And (remember) the Day (Allaah) will call to them, and
say: “’What answer gave you to the Messengers?’”

[al-Qasas 29:65]

If the Sunnah of the Prophet (peace and blessings of
Allaah be upon him) is clear, then it is not permissible for a Muslim to
ignore it because of the actions or words of some person. Imam al-Shaafa’i
(may Allaah have mercy on him) said: The people [scholars] are unanimously
agreed that if the Sunnah of the Prophet (peace and blessings of Allaah
be upon him) has become clear to a person, it is not permissible for him to
forsake it because of the opinion of any person. 

Secondly: 

The one who has become an example for people must be more
careful about his adherence to the Sunnah and not going against it, because
the people will follow his example and will regard his actions as being in
accordance with sharee’ah. 

Shaykh Muhammad ibn Saalih al-‘Uthaymeen (may Allaah have
mercy on him) said: 

Hence the scholars have obligations that others do not, with
regard to acts of worship, morals and manners, and interactions with others,
because the people will follow their example, they will follow their example
completely. Some people will even sit by a scholar whilst he is praying –
for example – and take note of every single movement. When Ibn ‘Umar (may
Allaah be pleased with him) grew old, he did not sit muftarishan (sitting on
the left foot and holding the right foot upright with the toes pointing
towards the qiblah) in the prayer. One of his sons said to him: “What kind
of sitting is this?” He said: “My feet do not let me?” Look at how the
people watch the scholar and take note of everything he does, and even what
he does not do. Hence it is essential for the seekers of knowledge to be
good examples in all things, so that the people will respect them. End
quote. 

Al-Liqa’ al-Shahri (introduction
to meeting no. 49). 

Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allaah have mercy on him)
said: 

The scholar is known for his patience, his piety or awareness
of Allaah, his fear of Him, his hastening to do what Allaah and His
Messenger have enjoined, and his keeping away from what Allaah and His
Messenger have forbidden. 

This is how the scholar should be, whether he is a teacher, a
qaadi, a daa’i who calls people to Allaah, or in any field of work. His duty
is to be an example of goodness, and to be an example of righteous deeds,
acting upon his knowledge, fearing Allaah wherever he is, guiding people to
goodness. So he should be a good example to his students, to his family
members, to his neighbours and others whom he knows, so that they can follow
his example in his words and deeds that are in accordance with the laws of
Allaah, may He be glorified and exalted. 

The seeker of knowledge must be very careful and beware of
being careless about that which Allaah has enjoined, or of falling into that
which Allaah has forbidden, because he may be taken as an example in that.
If he is heedless, others will be heedless too. The same applies to the
Sunnah, and to makrooh actions. He should be keen to observe Sunnah actions,
even if they are not obligatory, so that he will become accustomed to doing
them, and people will follow his example in that. And he should keep away
from makrooh things and dubious matters, so that people will not follow his
example in that. 

The seeker of knowledge has an important status. The scholars
are the elite in this life, so they have duties that others do not share.
The Messenger (peace and blessings of Allaah be upon him) said: ‘Each
of you is a shepherd and each of you is responsible for his flock.” End
quote. 

Majmoo’ Fataawa al-Shaykh Ibn Baaz
(2/312, 313) 

2. and he (may Allaah have mercy on him) said: 

Allaah says (interpretation of the meaning):  

“And who is better in speech than he who [says: ‘My Lord
is Allaah (believes in His Oneness),’ and then stands firm (acts upon His
Order), and] invites (men) to Allaah’s (Islamic Monotheism), and does
righteous deeds, and says: ‘I am one of the Muslims’” [Fussilat 41:33].

This verse shows us that the one who calls people to Allaah
must be a person of righteous deeds, calling to Allaah with his words,
calling to Allaah with all his actions. Hence He says after that “and does
righteous deeds.” The one who calls people to Allaah must call with his
words and with his actions. There is no one better in speech than this type
of person, those who call to Allaah with their good words and guide the
people with their words and deeds. So they become a good example in their
words, deeds and behaviour. 

This is how the Messengers (peace and blessings of Allaah be
upon them) were: callers to Allaah with their words, actions and behaviour.
Many of those who are called benefit more from the callers’ behaviour than
from their words, especially the common folk and those with limited
knowledge. They benefit from the caller’s behaviour, good attitude and
righteous deeds in ways they cannot benefit from their words which they may
not understand. One of the most important missions of the one who calls
people to Allaah is to have a good track record, to be a person of righteous
deeds, to have a good attitude so that his example may be followed in his
actions, words and deeds. 

This verse encourages and urges us to call people to Allaah,
and explains the status of the callers (daa’iyahs): they are the best of
people in word if they are sincere in what they say, and do righteous deeds;
they are the best of people in word and no one is better than them in word
at all. Foremost among them are the Messengers (peace and blessings of
Allaah be upon them), then those who follow them with insight until the Day
of Resurrection. End quote. 

Majmoo’ Fataawa al-Shaykh Ibn Baaz
(3/110, 111) 

We ask Allaah to set the affairs of the Muslims straight, and
to guide the daa’iyahs and seekers of knowledge to that which is in their
interests and in the people’s interests. 

And Allaah knows best.