Apple and Google stores are classic rent seeker behavior.

Deny them profit.

You don’t have to use the Google store though.

Apple forces you to the their app store, and they have a huge list of requirements they impose on apps to which really dicks around developers

You don’t have to use Google’s store, but they’ve done a lot of anticompetitive shenanigans to snuff out competition and ensure they remain the dominant storefront.

After Google saw how much money Apple was making, they seemed to immediately regret having Android be an open platform. It was a convenience when they acquired the product early on because they could bring it to market quickly, but they’ve done everything in their power since then to close it up.