We should totally make an IG Guild of Bards.
They could make deals with the Tavern owners about stage area, performance times and dates, tipping policies, etc. If it was organized well enough, you might be able to convince plot to have "the tavern" pay the guild to regularly put on shows (it would keep their guests entertained and draw more folks to add to their business).
Or, perhaps if we wanted the guild to get ducaly sanctioned we would have to pay the tavern to play there but got to keep all the tips... therefore the guild would need to charge a small fee (dues) to it's members.. but that went towards paying the tavern and taxes to his Grace (if such things existed). The guild members would "get something" out of it by being scheduled to perform.
The guild could even create policies like... if you play an instrument then you have to accompany a performer twice a year or something (to encourage better performances). Or.. if you only sing, you need to take an hour lesson of another instrument twice a year. The possibilities are quite endless. I've actually always wanted to build a small stage in the corner of the tavern (just a step up) that would encourage more bards, performers, cryers, and the like.
Hmmm (deep in thought)...