Gawd why was everything so hard and complicated? No, Bart, don't do this-- that's not how things are done. No, Bart, don't do that-- no one does that. No, Bart-- that's not "appropriate".
Apparently being friends and trying to help people to not feel alone was bad because High School. What did that even mean? That was the lamest excuse Bart had ever heard for a reason why he shouldn't do something. And beneath all that self-righteous teenage anger about how he could do what he wanted and Wally could just try to stop him, there was a growing seed of doubt and insecurity. Wally wasn't always right, but he was sometimes (if Bart had to admit it) and despite the fact that Wally probably thought he'd be better off if Bart had never been dragged to the past and saddled on him by Wally's Aunt (Bart's Grandma) Iris-- Bart was fairly certain that Wally wasn't actively looking to hurt him, or make his life hellish.
With a bit of reluctance, and one of those awkward looks that said I don't need your approval and I'm not even looking for it but incidentally if you maybe approved that'd be okay too because I'd like to know that maybe but only if you were already thinking it because I'm sure not going to ask because I'm a grown man Bart reached into the cart to grab the heart shaped boxes-- then in a blur they and the wrapped paper and ribbon were gone and a few milliseconds later, Bart was walking alongside the basket again, hands stuffed in his pockets and a pensive look on his face.
He'd have to find something else for Valentine's Day then-- and not bother Wally with it. He and Linda already had to feed an extra gaping mouth, they didn't need any other burdens (particularly not money-related) on top of that.
"I'll think of something." He relented, not wanting to fight-- or talk-- about it anymore.