If you also have gone through this decision process, what has swayed you one way or the other?

ANY time I've had a legitimate shot at staying out for several weeks, rather than shorter times, I've taken it. The whole quality of the experience changes as the days go by and you never see a road, car or building, and never hear an unnatural sound aside from the random airplane.

...I keep going back to the through-hike as more aesthetically pleasing....Were I wealthy, this would not even be an issue.

I think these two quotes really isolate the crux of the issue. In the long run, spending $500 or $600 is what stands between you and doing the hike you really want to do. If I were you, I'd look at what that money would be needed for if it weren't spent on the outfitter resupply, and decide based on priority.