In this report from Iraq, it is said: "While they wait -- Marines talk, smoke -- but most of all, they dip. The most common sound around Camp Abu Graib, next to a weapon being cleared or an incoming rocket (usually one per day) is the sound of a can of tobacco being tapped loose for the next pinch."
Tapped loose? Having studied these matters for 20-some years, I always thought the point of smacking the can was so that yer Skoal or whatnot gathered in some depth on the low side, facilitating the pinch. (That's the kind of language mostly used by tobacco-fanciers: pardon me, while I facilitate my pinch.)
This subject matter has caused me to recollect a Government Services Administration report on the federal courthouse at Big Stone Gap, which opened around 1920 and reopened around 1980, and this report (compiled in the late 1980s) included a letter from an early clerk to the Administrative Office of the United States Courts, and the gist of the letter was could you please send us here in Big Stone some more spittoons, at the last session of court everyone was chewing and spitting their tobacco juice on the floor and it was quite a mess. (I imagine the administrative office still gets letters like that almost every day.)
I've never seen anyone spit tobacco juice at the Big Stone Gap courthouse - at least not on the floor. That GSA book was a very interesting book and I've been secretly plotting to get a copy for myself, if that's possible, from the GSA through FOIA or by some other means, but it may not be possible. One of my law school classmates is some kind of GSA lawyer but I've not yet got up the nerve to raise the matter with her.
As the pre- or post-modern alternative to Copenhagen, this BoingBoing post describes betel nut chewing.