It also requires exponentially more stuff to be active year around, and adapting to a full time work/weekend schedule, compared to temporarily with a flexible schedule.

Just the beach walk will require a whole wardrobe of suitable clothes and shoes if you want to do it year around and live in a place with seasons. The scooter doesn't work in the winter.

Renting things also requires you to have a flexible schedule and be outside of the normal work week/weekend, because on a sunday when the weather is nice, everyone wants the stand-up paddle board and all the other stuff at the same time, that's the whole point of owning stuff, that it's there for you when you want it. Renting always means you get it when (most) other people don't want it.