You can get the same endorphins with exercise, but you don't get to see the results of your work. It's so much more satisfying when you can clearly see your progress. Playing in sandboxes or digging holes in your yard is a game, but manual labor alone is often just work.
I haven’t been to a gym since leaving college (I rowed in a championship 8, and twice daily workouts were a thing). Instead I do manual labor and love it. I’ve built dry stack basalt walls, mowed, edged, pruned, chopped and sawn, poured and broken cement, etc and never missed the (for me) pointless repetition of “exercise”. I respect folks that can do it, but I can’t understand how.
Yeah, that's part of why those gameified exercise apps are such a big hit - you can see "results" before you see the results!