In the late 1950's, Esso had more than 10,000 stations  and #2 British American had 8000+ across Canada. Now, Esso's count is 1700 while Petro Canada (BA's retail successor) has about 1500.
Reasons? Vehicle reliability: gas bars, not service stations, increased gas mileage and thin margins at he pump (more profit in the attached stores).
Don't panic - we'll all survive somehow.