Well there's a big difference between the option of paying for cosmetics (that can also be earned through play), and the option of being able to buy sticker packs that not only unlock new characters, but also give you skip challenges to raise your rank. To be honest I even despise the route of paying for cosmetics, especially that can't be earned through play, however when you start getting things like skip challenges to raise your rank what's the point of having a rank showing in the first place? Exactly.
And RaineyKins, this isn't about maturity level. If I want to play in the welcome mat I could do so and do even better than I already do in GaG mode. This doesn't affect player skill I'm aware of that. I am good enough already to be competitive in the game. What bothers me is that it allows you to skip your way through the ranks, completely undermining the ranking system.