I have gotten about 99% of my kits on the second-hand market, and of those, most were bought via eBay, then via model shows, and then via my club, in our raffle or gifts and swapping between members.
You're right, HobbyTown has a limited selection, as do the other big commercial sources around here: HobbyLobby, Michael's and AC Moore. They're all general hobby stores, though, not scale modeling specialty stores, and so, I understand that they don't generally carry the kinds of subjects that many of us might want to build.
Playing Captain Obvious for a moment-yes, the Internet has made a much broader selection available to us, than in the days before we all got wired. So, I go to the bricks-and-mortar stores for many basic supplies, and I'll ask them if they can order something for me-whether a kit or supplies-but I don't expect them to be able to get me the latest Wave Maschinen Krieger kit.
Even for basic supplies, though--my local HobbyTown sells Tamiya paints, for example, but if they don't have a color I need, then I have to decide if I want to wait for them to order it and have it arrive, or if I'll just order it online direct from Tamiya USA. It all depends.
Best regards,
Brad