Should this make a difference? Just because users don't actually use alternative app stores doesn't mean the alternatives don't exist. It's not like Bed Bath & Beyond gets to complain that they don't get as many customers as Target. It has to be okay for a company to find themselves with naturally large marketshare simply because they do good business. If Google is doing something unkosher to get/keep their marketshare (and they are) then that's what you have to go after.