Those are just statistics and don't have anything to do with gas.
Canada is a country of 35 million bordering a rich country of 350 million.
Yes and if (1) gas in Canada were cheaper than in the US, and (2) the border between the countries was completely open, then you’d indeed see people going to Canada to buy gas.
Driving over a border in Europe happens without you necessarily noticing.
That isn’t true of US borders.