How they make their money is their business, but paying for premium, boosts or any other ingame power up is essentially legalized cheating. Players should be on a level playing field. I'd rather have the game be completely free and rely on making money from advertisements or cosmetics, or just make it a monthly subscription game. Personally I'd prefer a free game, with an option of paying for cosmetics, but even a pay to play model is better than pay to win.