With Prince Rupert as a gateway to Asia for imported goods, what else is it a gateway for? Illegal drugs? If so, Asian gangs and motorcycle gangs running that industry would need to travel up and down the Highway of Tears to Prince George. These same people run prostitution rings.
As far as legitimate imports, truckers use the corridor. The car ferry also lands there. So, isolated as it may appear on a map, the highway sees travellers from near and far.
Thinking of the highway out of Dawson Creek, this is Mile Zero of the Alaska Highway. Again, isolated as it appears, this route serves as a transport corridor for goods and people bound for Alaska. During the summer months, this road sees travellers including tourists, Alaska residents and personnel and equipment bound for the military bases. Some take the QEII north through Edmonton, then head west through Grande Prairie, Dawson Creek and north through Fort St. John. Others travel by car ferry, landing in Prince Rupert, going through Prince George, then north through Dawson Creek and Fort St. John.
Tourists are summer travellers for the most part in the north. The regular traffic, people who are familiar with the area and communities along the way, is year-round.