I don't think it has anything to do with size or population. Compare Canada with Australia. Canada's area is roughly 10 million km^2. In 2015, the population of Canada was ~36 million (3.6 people/km^2). Australia has an area of 7.7 million km^2 and a 2015 population of 24 million (3.1 people/km^2).

These numbers don't even take into consideration of the fact that 75% of all Canadians live within 200 km of the US border. Assuming the population in the south subsidizes the cost for expanding to remote locations it's hard to believe we need to pay as much as we do.

Canadians pay too much because the big companies like Bell and Rogers control the networks and push out competition. They charge as much as they want and we just accept it.

I currently do not own a cellphone (even though I'd like one) because I'm not willing to pay the fees.