I assure you, Michael, it's not a macho thing. I prefer to walk. If I'm too tired to walk, I'd rather not play golf. And yes, when in Bandon and playing 36 holes a day, my muscles definitely do ache (but it hurts so good).
I once saw an old codger (he must have been 75 easy) playing at Bandon. He was wearing plus fours so he was hard to miss. We were walking into the clubhouse after playing a morning round at BD; this was during our second day of 36 holes-a-day back when you had to play the repeat round at the same course. We were hurting. Then, we saw the old man literally sprinting out of the clubhouse to the first tee to begin his second round of the day.
Since then, I've resolved to do two things: first, never complain about walking on a golf course; and second, try to enjoy life as much as that man.