I must admit, I do look out for snuff taking in films, and have noted it in the following:
The Adventures of Baron Munchausen Scarlet Pimpernel Waterloo The Libertine Bagdad Cafe A Matter of Life and Death Most of the Sharpe series Some Sherlock Holmes films, etc...
And I'm sure that there are others, that I seem to have let slip from my mind, at this time...
There was a scene in one of the Final Destination movies where I'm not sure if the character was supposed to be doing snuff or cocaine, I wasn't watching the movie, so for all I know he could have been someone who was known to be strung out, I just happened to walk through the room when someone else was watching it and saw someone sniffing from between their thumb and index finger... and it reminded me of snuff.
If I remember correctly in one of those Final Destination movies, the one where there was a big car pile up on the hwy. There was a guy who was driving and he put a bump of cocain on his hand so he could take hits while driving. He played the cliche druggie guy that dies.
the madness of king george has a scene where rupert everet either is using snuff or smelling his fingers. The movie Auntie Mame has a southeren woman who use snuff in a very unflattering light, for one thing she sneezes after every pinch.
Bleak House is great. I've seen it twice, but wasn't snuffing at the time so I didn't notice. I guess thats a reason to watch it again. It's odd seeing a gaunt Gillian Anderson.