Is this gaslighting? Or something else? Partner (m46) aghast at my (33F)

My boyfriend offered to go to Kroger for me because I was busy with school after my full time job . It was 4x fuel points Friday, so I asked if he could keep my stuff separate (only 6 items) and use my Kroger number so I could get the fuel points from my own purchases with my own money.

He genuinely acted like this was a completely ludicrous request (like wtf). Then he asked if I could just send him the money. I said that if I was paying for my groceries, I wanted the fuel points, especially because I drive SIGNIFICANTLY further than he does to work (he has 5 min one way, I have an hour). I also am younger, make less money than him.

He eventually said he’d just buy my stuff, but his initial reaction really bothered me.
It’s not really about six groceries or even the fuel points. It’s the lack of consideration.

Instead of simply thinking, “Sure, no problem,” his reaction was essentially, “Why would I do that?”
These are the kinds of small interactions that really get to me because they make me feel like I’m constantly having to justify why I deserve basic consideration.

If the roles were reversed, I wouldn’t hesitate to do this for him. In fact, I’d probably automatically use my fuel points for him if I knew he drove substantially more than I did.
I know this sounds minor on paper. But isn’t consideration in a relationship largely demonstrated through these little things?

Im actively planning to leave him. The last year living with him have been death by a million paper cuts.

He has a lot of weird rigid behaviors that I was initially explained away by quirks, but I'm really starting to think it's intentional