I've often told the story of the two locally owned stores nearest to me. One is owned by a musician, the other is owned by businessmen.
I wholeheartedly support the former store, I'm friends with most of its staff, and they stock a decent selection of heads and sticks. Since they have a good relationship with D'Addario and Zildjian/Vic Firth, I try to route purchases through them whenever possible. They will reach out to me if they're restocking heads or stuiks to see if I have any special requests, and I really appreciate that personal touch. I may pay a bit more, but I'm happy to do so.
I avoid the other store. Their drum selection is geared towards the school band consumer, with marching heads, sticks and mallets crowding the drummers' corner of the store. Their merchandise is stupidly highly priced (sometimes 150-200% markup from internet street price), and nobody there plays or knows drums at all. I went there the other day to see if I could find a coated snare head. $37.50 for an Ambassador?!
If it's a drum or cymbal I'm looking for, I *might* drive the 3 hours to Seattle to go to a Guitar Center (or more likely Donn Bennett's). I also buy used a lot. If it's an item that will be the same no matter where I buy it (stand, pedal, etc.) I will not hesitate to buy it online if there's no good local option.
The success of the mom 'n' pop store is (approximately) one-third loyal customer base, one-third good business practices of the store owners and one-third market viability. If one is not present, the store is pretty much doomed.