After the 1973 oil crisis, European countries have progressively increased taxes on gasoline as prices were coming down, in order to keep prices up. It's quite clear today that Europeans generally drive a loss less and buy a lot more efficient cars than Americans. Also, the cost of energy in general is quite higher in Europe and Europeans consequently adjust their energy usage. Putting a timer on the hot water tank (so that the water is only hot during the part of the day when you need hot water, e.g. morning shower) is something I had never seen before going to Paris.

So we know that taxation can impact consumption levels and create new habits.