Of course, many people have. I bet you'll hear something along the lines of:

"Spending in Mech Arena is optional..."

Hello! Our prices are standardized for all the platforms (i.e., Play Market, AppStore, Plarium Play). What we do is set the baseline in prices for our products, but the end price is affected by a lot of factors, such as local conversion rates. And that is something we can’t influence as that’s how prices for mobile stores work.

Besides, some of the Offers are generated personally for you according to your game experience and other factors. In this case, having something more expansive means that you may have something else cheaper.

I'd recommend you keep an eye on the Offers and Mech Arena Store, as good promotions appear there from time to time!