I have Muslims in my family, and Muslim friends, and their attitudes towards alcohol vary greatly.
Most that I know wouldn’t drink alcohol, but would sit with others who were, so long as it was accompanying meals, and not in copious amounts either.
Some would make excuses not to attend the function if they knew alcohol was being served, or ask if it could be changed to an alcohol-free venue. Others I know sell alcohol as part of their business, but don’t drink it themselves, whilst others enjoy a drink or two in private, but hide it from their family and community.
I’ve known some in the past who would go clubbing and take recreational drugs, but would refuse to drink alcohol (I’ve never understood this!).
I guess the opinions vary greatly from Muslim to Muslim, but I do believe from experience, that there is a monumental amount of pressure and worry for many that they must be seen to be conforming within their religion and community. Sometimes this is self inflicted, and other times it isn’t - just another variation.
I know Muslims who pray 5 times per day, those who only pray on Fridays, and those who last prayed on Eid.