I don't even see Batman Returns as a sequel to Batman. The only references to the first is the Vicki exchanges and Penguin's speech about boy scouts becoming clowns (unless he meant the Triangle Circus Gang). The look and feel of everything is radically different, not that that's a bad thing. Wayne Manor isn't the same, it's a completely different mansion. Gotham City no longer resembles Furst's world but Bo Welch's creation. Then you have the Batcave. The single suit and vault idea is replaced with a draw bridge type entrance. Instead of one, one of a kind suit, Batman now has several. No turntable, no notable similarities. I may be wrong but I seem to recall Burton scoffing at the idea of this being "sequel" or a continuation of what was done for the first. I've always seen Batman Returns as a sort of revamp of Burton's first take. Other than the actors and the Batmobile there isn't this sense of continuity whatsoever. Batman Returns is it's own world, sort of like Batman is in it's own world, at least that's how I've always seen it.
When I watch Batman Returns it's just not something I think about. There's this newness to Batman Returns, this other worldly quality that the first doesn't have (well the first has it's own, but it's not like Returns) and I don't think the snow is because of that. I'm not really into continuity, I like to view each film on it's own merits and stories. Even with the Nolan films I don't really view them as continuations but as their own thing.
