lets be totally fair here...MOST WALLPAPER APPS CHARGE A FEE OF SOME SORT...be it a one time fee (less likely nowadays) or a weekly/monthly fee. Not all of them are worth it, most arent. So was marcus doing anything that wasnt done before? No.
He was trying to make a few extra bucks, and people jumped on his back for it. Ok. heres the funny thing. You can bark all you want about the unfair price he was charging for a wallpaper app subscription, BUT at the end of the day you dont have to pay for it.
Heres a prime example. I love my Apple Watch Ultra 2. Paid 400 dollars or so for it with a trade in from the first one. I doubt ill trade in this one for the 3rd gen as i dont see the upgrades as useful to me. Ok, but i love the watch and all its functionality.
They do sell far more expensive watches that do far less then the apple watch. Your not likely answering phone calls and texts on your average low end rolex are you? Unlikley. Yet they charge WAY MORE those watches then you would pay for a full retail priced Apple Watch Ultra.
Now one could argue the quality of the material, etc...but at the end of the day, you still get to chose between a more functional if not less fashionable apple watch ultra (or lower end model) or pay way more for just the look, material, brand name and social status of a Rolex.
That choice is yours and yours alone to make. Same thing with the wallpaper app. You can chose not to buy it, and apparently enough people chose that and now its getting shut down.