I'll be that guy - I'm a working player. As Paulie Walnuts once said to Christopher on "The Sopranos", I ain't running a school. My standards are high, and I don't enjoy playing with those that don't have an experience level, seriousness of intent, or personal time investment into playing that is roughly equivalent of mine. It's impossible to sound competent and professional if the other band members aren't as well. I honestly don't find myself in situations where there's an obvious weak link or beginner level players anymore. All that said, as I ascend to the undesired title of "elder statesman", I advise and counsel younger players all the time.
Of course, I played with musicians much better that me when I was younger. However, I respected the group effort by doing my homework, practicing a lot by myself, and bringing an acceptable time feel and instrumental ability to the table to start with. I also preferred to just watch and learn if the musicians involved in a gathering were doing stuff beyond my ability back then as well.
I couldn't say it all any better.