"Would it really hurt to put a few reloading presses in a scene every now and again?"
There were, in the main storage room at Woodbury. Looked like Lee Precision products.
That said, the show's not supposed to be "The Gunner's Video Guide to Surviving the Zombie Apocalypse," so they're not going to go into crap like "Rick, I couldn't find any Winchester Super-X 158-gr. jacketed hollow point in .357 Magnum, but I did manage to find some 135-gr. .38 Special +P Speer Gold Dot."
I have NO doubt that were you to say "Speer Gold Dot" to the cast, 95% of them would glaze over, 4.5% of the remainers would look vaguely confused, and .5% of them would know what you're talking about.