If you really want to talk to the dudes, I've found that some of them would be more than happy to answer all your questions and then some. The key to making this happen is to go there when you know they will not be too busy. Or sometimes I'll just browse until the store mostly clears out and there will be less chance of interruption. Just make sure you keep xcrispi's "flowering plants" rule in mind and everything will go fine. The first time you let weed talk slip will probably be the last time you get any extra tips, and quite possibley the last time you go into that store.