Mobile games get a lot of bad reputation from the predatory systems with loot boxes and freemium models. I don't deny that there are some bad and worrying things in these systems. They can be addictive and some people might end up spending way more than they could afford.
But these systems might be the only true trickle down economy systems that actually work. The only reason these games can offer a free experience is the big spenders who practically finance the whole development of these games.
While making these games practically free for everyone else I think it's just fair if they get some advantage in the game. I mean if you are willing to drop 110 000$ that it takes to fully max out a Diablo: Immortal character you should be able to win more. Besides, even that probably doesn't guarantee the number one spot in the rankings, there are definitely others ready to drop such amounts from their pocket money to gain some advantage. While those rick kids are fighting among themselves I'm getting my moneys worth of enjoyment from all the free content that they enabled. There are two completely different games going on.