Not to get hate on this, but even tho i m not spending money myself i believe that people who spend money in this game should have an edge over the people that don t spend.
In order to benefit the 70% training on players over the age of 26 they need to have quite a lot of greens, and i don t think that many people that spend money in this game watch ads everyday for a full month to gain 700 rests when they can simply pay for them in real life currency.