[realusername]

> . Is that fear unfounded?

Yes, either they have a strong sandbox model or they don't and the appstore won't help either way.

> What prevents this from becoming the case?

Same as in real life, you can buy products at different supermarkets...

[isykt]

Do you prefer having to physically go to different stores to get the items you need?

[realusername]

If that avoids me paying a absurd markup because there's a supermarket monopoly, yes it's definitively preferable.

Most generic stores have everything though.