What makes a rentable scooter easier to park than a rentable bike?

Scooters are smaller.

Because you just leave them wherever.

Edit: Not voicing approval for this practice but that’s how it seems to work in my city at least.

But why couldn't you do the same with a rental bike? Also not approving, just asking.

That's a city planning problem, though. Designated small-vehicle parking that isn't explicitly for bikes seems like a good idea to have. No reason bike storage should be bike-exclusive

The scooter companies are free to fund installation.

Honestly, I think scooter companies should be fined for any scooters left in a place that causes problems. It's essentially litter, so it should be treated as such. Scooter companies should be providing some means of locking them up securely and expect their users to use them.

I doubt there were many parking lots when cars were new, too.