I have had the distinct pleasure and tremendous opportunity over time to sit in with some jazz groups in small intimate gigs. If I would have pulled out the fake Book it would not have been received well. So I would just Fake it. Maybe times are changin. Just sayin.
different situations suggest different tactics. When dissenting opinion is the majority opinion, I'd go with the majority.
When its a mixed bag of opinions, I'd go with whatever I prefer.
Bottom line, if you HAD pulled out a fake book, what's the worst that could have happened?