If you work out of your (legal) home?
I have seen many people talk about (not just at CC) having tastings at Panera. Do you just meet people there or do you need to ask permission to do this? (If you plan on offering customers your food/cake while there)
You can always do a traveling tasting, meaning you meet them at there place. Makes it intimate and nonintimidating for them. They are more relaxed in their own surroundings. Yes it is a bit more of a hassle having to pack everything up, but if you put your samples in totally disposable packaging/display ware then it is really quite easy.
If you do them at a local coffee shop, etc. I would ask the mananger/owner permission. From my experience as long as you purchase something they don't have a problem.
I do them at my dining room table. I prefer it that way because I often get out my pans to stack them and give a visual.