[chesimov]

I exercise because it's fun, and allows me to do fun things like hiking in the wilderness. It's much more fun to hike when fit. Also cardiovascular exercise improves many aspects of brain function, which I'd regard as a plus.

[ImaCake]

I like exercising too. But I specifically like doing it outside. The gym has no appeal to me because I like being a part of the wider world when I exercise and feel that paying for the privilage to exercise is ridiculous.

A more nuanced critque might consider whether some forms of exercise have a higher cost than their reward (e.g. they are really boring or expensive).