Agreed on all counts (and I certainly look forward to going into town when I'm on trail too ...). Thru-hikers typically carry a week or less of food at a time (which is more like two weeks of food for a person with a more normal metabolism, FWIW). My longest carries have been eight days. But a person doesn't have to spend a great deal of time at town stops; that's an individual decision, some folks are good at getting "in and out" (and sometimes that's motivated by limited funds).

But I agree that it would be a somewhat yet-different experience just purely staying out for weeks; some would thrive on that, I think that for many it would at best take some getting used to. Probably a bigger factor along this line for the long distance trails is which trail you're hiking on --- I had many more true days of solitude on the CDT than the times I walked alone on either of the PCT or AT.