If the store is small, placement of fabric is important. I have left a store because a class is in session and quilters are busy working in the fabric area and I don't want to ask anyone to move out of the way so that I can look at fabric that is behind them.
A mirror is essential when classes are taught. Someone might want to see the length of a handbag strap against their body - or the length of a jacket, its sleeve, etc. etc.
If classes are given at lunchtime, avoid bringing in smelly foods. Being around fabric is sensual and the odor from food, no matter how delicious, is a distraction.