Why did the front plug/connection come into being on TCs?

Don't know about TCs today but back in the 60s there were doors into the wheel well areas. Open the front wheel well door on the drivers side and plug in the TC. Easy access, short wires and out of the way. Plus with the 10 1/2' TCs that dropped down in the rear you didn't have to crawl under trying to plug it into the rear socket. Most of the PUs during that time had sockets in the front and rear. A trailer could be plugged into that rear socket since many of us towed boat trailers behind our TCs.