Impossible to level up after certain level without spending big money

I really tried to like this game but like many reviewer wrote this game is impossible to play if you dont spend $100 a week. You can play up to maybe level 20 without spending money if you dedicate lot of time paying but after that it becomes impossible to level up no matter how many hours you play. What a waste of time...

Dartanianlee about VEGA Conflict, v1.88787