If you go to lets say Vegas, and they have a Roulette table, they say you can play for free, yet win money. Do you seriously not consider this gambling? You DO NOT have to pay to gamble. Gamble means RNG, it means doing something with a random outcome!
Elder Rifts with free crest is a free roulette table, still gambling.
Elder Rifts with paid crest is a paid roulette table, also gambling.
So gambling exist in DI regardless if you pay for it or not. You cannot hate a paid roulette table without hating the free one too if you hate gambling.