Have to say I agree. I've been to two Batteries Plus (which is apparently Batteries and Bulbs now) and they know about as much about batteries as the screen tells them. They do carry 18650's, but you need to know exactly what you're looking for, or read up on what they have available before you buy them.
If they don't have it in-store, they can order it, but you still need to make sure you know what you want and verify it before you pay for it.