Here are my honest thoughts. Keep in mind that I have no business sense.
The only shops I see really making it are one of three types:
1) Online/Internet sales only. High volume/low prices, zilch for customer service. More on that later.
2) Established shops that have a large following of old-timers. When the older generation isn't around any more I expect those shops to disappear too.
3) Shops owned by people famous within the hobby. People go there to get their specialized knowledge. Obviously a guy won't give you the time of day if you're buying everything from Tower and bringing it to his shop asking him how to put the ducted fan in and never buy anything from him.
Customer service is a huge plus. When I was a kid and just getting started, the guy in the shop would drive to my house to help me build my model. Then he would drive me to the field and teach me to fly. It was a long drive from his place to mine and the field was going the other way from where he lived. Obviously he went far out of his way to help me out.
The shops I go into now won't even stop playing with their personal model long enough to point me to whatever I'm looking for and I have no desire to buy from them. If the folks in the shop take the time to listen to my war stories and help me out then I'll buy from them. But when it comes to high-dollar items, I have to buy mail order or I'd be priced out of the hobby. I don't mind spending extra on fuel, glow plugs, covering, and other miscellaneous items at the LHS because I do want them to stay in business.
I'd love to see people taking an active interest in the welfare of the hobby rather than getting a quick fix with arf's, internet shopping, etc., but I think that's going to be a long time coming.
In our club people ***** about paying $30 dues every year and we have a great field right in the middle of town protected by a huge property that will never be commercialized, so as long as we don't tick off the owner, we're golden for a long time to come. Point being that some people just never appreciate anything but they expect a lot and that will be something you will have to overcome.
I wish you all the luck though. I'd love to see a good, well-stocked shop with people truly interested in helping hobbyists in every town in the U.S.
Oh yeah... as JoeyM said, if you are dedicated to cars or japanese action figures or whatever the latest craze is you'll do fine. It's R/C aircraft shops that seem to have trouble.