I apparently have won the battle.
Our DM came to our store earlier this week for an issue entirely unrelated to this whole white coat thing, and he didn't care if we wore the coats or not. Therefore, the wonderful store manager (note it wasn't a pharmacy manager) who chastised me last week for not wearing a coat can go blow himself.
The best thing is that my pharmacy manager also never wears a white coat. In fact, he hasn't worn one in 20 years, and he refuses to wear it too. Now the store has two pharmacists openly defying the new dress code, and there's nothing they can do abou it.
It's really nice to be able to stick it to your store managers every once in a while. I mean, I know it's a relatively insignificant thing, but I'm sick of them determining pharmacy policy. I'm sick of them overruling our authority. I'm sick of them handing out gift cards to asshole customers who complain simply because they don't get their way on something they're obviously wrong about.
It's just a small victory, but it still feels good.