Aren't you paying for access to the customer base, rather than just a webpage and checkout? Not many people would be willing to side load apps from third party websites.
Moreover, while location (e.g. access to customers) is a good portion of what makes rents in the same locale different, the costs and risks of providing the physical location are higher than providing a webpage and checkout (of which the marginal cost is basically $0).
IMO your argument is NULL, if there were alternatives like an Open source store, a Google, Microsoft and Amazon store on iOS you would not be forced to use them. Check the Android model, most people are using the Google store and the GIANT benefits is that if Google decides or is forced to not allow an application you are not screwed, you can go around that.
Again, if you want to consume ONLY Apple approved content then nobody would force you to not do it, see Android.
I actually agree with you on the fact that having other stores on iOS would not stop people from just sticking with the App Store. That’s true. My concern about forcing Apple to support other stores is the ‘forcing’ part.
People, throw around the term ‘forcing’ companies to do this and ‘forcing’ consumers to do that very liberally in situations where nobody is forced to do anything, but this is different. Apple doesn’t want to implement the APIs, security controls and services to support third party stores. Mandating that they do so would literally be forcing them to do development and testing work, and support features they don’t want to support. Presumably such a mandate would also have to specify exactly how such features must be designed and implemented in order to be compliant, so now we’d have government specified features and UIs. To me, that seems a few steps too far.
When companies do anti-competitive things they are forced by the society with laws to stop, without this kind of laws we would still have mobile phones that are locked forever to a network, still have a big tax when you call someone on a different network, still have a big tax when you would transfer to a different back or use other bank ATM(this examples are from EU not sure about other regions).
For example the laws related to preventing fires also FORCE companies to add more exit doors, use the correct materials, add fire suppression equipment etc. A few years back some night club bribed the fire department and opened without respecting this laws, around 100 young people died because some greedy bastards didn't want to do the correct thing.
Anyway, my comment was about the argument "I love Apple to protect me" that argument is NULL.
We can attempt to debate the actual market share of Apple, to define the actual markets, to decide if Apple and Google are actually competing or have an hidden agreement, to define how we measure the damage by the market abuse (if any), to determine fixes for this abuses (if any).