I feel like in some of these bigger places they get a bit jaded. Sometimes I feel like they run the gambit from just plain rude to super helpful. At one place in Austin I won't name, I've been there and they've talked to me like I'm an idiot and they've also treated me like a person at other times. It just depends how busy they have been that day. I have a feeling that at certain times they get waves of idiots and so they kind of get used to approaching everyone that way.
In Kerrville, there's Young's Guns on 16 North, Gibson's Discount Center (my favorite), and one down by Dairy Queen on Hwy 16 (can't thing of the name). And there may be others I'm not familiar with. No nothing about Leon Valley.
Keep heading out of town on Bandera past 1604 and a few miles outside the loop next to Chaparrel Mexican restaurant is the Gun Shack. Great folks, good selection, fair prices IMHO. At least swing by and see whats up.