A few comments on Jim Shoe's posting.
Many places (except a large number of provincial parks) will accept credit cards so there is no need to carry lots of cash. Also, you can draw local currency from your bank account using you bank card at many ATMs that are open 24/7.
Fuel has been sold in liters for many years. For pumping gas, self-service is getting to be the norm.
Tim Horton (widespread) and Starbuck (present mainly in cities) tend to attract a different clientele.
As for food, the law requires the price to be displayed per gram or kilogram but most stores will also display it per pound, often in larger numbers.
Alain
PS: Remember that the laws regarding firearms are quite different in Canada.