Jason usually isn't big on holiday traditions. It's just never been his thing. Like okay sure he appreciates 'em well enough when they're done - who doesn't like getting a big tasty dinner, and even he can appreciate pretty lights on occasion, and of course he's gonna do gift exchanges he's not the freakin' Grinch. He's just usually not going out of his way to do all the little extras on his own, you know?
Pumpkin carving, though? This he can get behind. Look, he is at times a simple man. Put a knife in his hand and tell him he's free to go to town on some big ol' gourds for the fun of it, and he's having a good day. And hey, it turns out, when he wants to be, he's surprisingly artistic.
At least, he can trace a picture onto a pumpkin and then carve it out without making a mess of things. He can even do some of the fancier detailing. He likes creative jack-o-lanterns. Also you get to roast the pumpkin seeds when you're done. And then there's pumpkin pies on the horizon, and Alfred makes a mean pumpkin soup. He just kinda likes pumpkins, okay?
"I'm not doing all bats this year, I don't care what anyone says about it," Jason states immediately as he eyes his chosen pumpkin up and down, sizing it up. "We already covered the whole fence in paper bats, we gotta branch out a little bit." He leans to peer at you around his pumpkin, grinning faintly. "Think Bruce'd freak if I put Supes' logo on one?" He would totally say Dick did it.