Some random questions driving through Canada to Alaska

Provincial & territorial campgrounds generally require payment in cash. All the gov't campgrounds in Yukon are on the trust system - put your money in an envelope and deposit it in a secure box.

In B.C. during the summer, generally someone comes around in the evening to collect payment, but some of the more remote ones are on the trust system too.

In B.C. there's a fee for firewood, cash required.
In Yukon there is no extra cost for firewood.