I do the same. For some reason goofy feels more natural when skateboarding but regular seems more natural when snowboarding. I'm right handed but do many things left handed( opening doors, using phones, shooting/dribbling basketball).
So glad I found this thread. I'm a snowboard n00b - just started this season - and I've been lurking here a while.
Anyway, I surf regular, so I assumed I'd snowboard regular too. Then today, I can't remember what I did, but somehow I started going down the hill goofy. And it felt more natural, and like I had much more control. Then I kept switching between regular and goofy (regular bindings tho), and I think I really do prefer goofy.
I tried to do a goofy pop-up when I got home (like in surfing), and it didn't work so well. I think I'll stick to regular with surfing. But I'm glad to know that some people do use different stances for different board sports . . .