My PC is a single purpose device, and that is for gaming. Which considering I use Steam for many of my games (not all) that 30% commission is already there.

The reality is many people use their PC's far differently than they use their phones. When my PC was my primary computing device many of the things I use and pay for on my phone either simply didn't exist, or I would never dream to pay for them.

Also you are missing the point, my phone becomes less useful because I flat out refuse to hand over access to my phone to a company which wishes to abuse that privilege of an alternative store. If they were going to act the way I want them to act, they would have no reason to use an alternative store.