Radio is Free But Risky for Retail Stores
Why not just play radio to avoid performance rights?
1) Loads of commercials - If you're not careful, you'll probably advertise your competition inside your own store.
2) Genre specific - You won't have control over what songs are playing. Songs will stop at certain points, when you least expect it. You're probably better off not playing it at all.
3) Amount of Talk - DJs can and will interfere with the mood inside the store by talking.
Your store is one place where the big R shouldn't be in.