Thought about a couple cases of his favorite beer. Still might do that. Any other ideas?

Consumables that the person already likes make great gifts, since they will get used up and not sit around.

I usually avoid abusable substances, just in case the person has a carefully balanced relationship with that substance.

But you know your friend.

Sometimes I just ask first. No real reason this needs to be a surprise.

“I know you said you won’t take cash, but I’m going to grab you two cases of X as a thank you, on my way back.”

Then they get a chance to call me off, or redirect me if it would be a problem.

And I’ll always let them call it off with even a mild “no thanks”, since they might not want to say to me “I have a real problem with X and I can’t safely have thay much on hand.”.