Skarpi raises a pertinent point (I'm fond of alliteration). Sessions are sessions are sessions. They are for musicians to play, learn and share. I'm very annoyed when I ring a venue in advance and ask the specific question "is this an open session, are all musicians welcome" to which I usually get the response "yes, totally open"...only to arrive and find that the people who have been hired to be there every week just to assure that someone is there (and you people, don't fool yourselves by thinking you cannot be replaced) are playing in Eflat and can't bring themselves to look you in the eye let alone greet you and welcome you when you arrive with your instruments. Lately, I just say "you obviously don't know who I am" which causes them to reflect, and I hang in like a rat terrier. Some people don't have the chutzpah to do this and often listeners miss out on the opportunity to hear/see something or someone "fresh". Shameful and shocking (more alliteration!). Keep the faith, be strong and move forward always!