just think about it for a sec, if the "op" items (brown boxes, silver boxes, skill reset, white stones) are not in the cash shop, where they should be? Its super awkard to obtain it from drops.
Also the "cashers" can buy dogis and sell it for zeni to buy "op" items so with that argument dogis should not be in the cash shop, the old game had all this items at the cash shop and no one complains about it
Why is it awkward to obtain from drops??
It gives you incentive to push through the grind XD