Hey Wolf, if you missed that one, I would have to question just how much working you've been doing; no offense intended. I suspect your idea of "working musician" is different than mine. Truth is that for working musicians (those who make their living playing music exclusively and nothing else; and have done so for many years) not every gig is a "fun fest". There are a lot of great projects, some not so great, and some that are a drag. The joke (and it is a common one) is emblematic of what is, unfortunately, a common and negative attitude on the part of many working musicians that unless they are part of a project that they deem creatively worthy at the highest level, even an opportunity to simply exercise their craft is cause for negativity. On the other hand, many who are always scuffling to find a gig, any gig, are tickled pink when one comes along. Here's one of my favorites:
http://s276.photobucket.com/user/tinasponsler/media/farside_banjo2.jpg.html
http://s276.photobucket.com/user/tinasponsler/media/farside_banjo2.jpg.html