Some people don't have the patience to save or maybe like myself have a 50 stash and decide to 'go for it'

Occasionally I get a random urge to roll a few, got 2x6* from these random 5/10 gem rolls, done about 4 so if I get a desire to roll I roll with it, besides, it's 0.45 of a gem 'more' per spin...so yeh it adds up over time but no wrong way

...as I've progressed I'm more inclined to save for event rolls like 20% chances at 6*'s as my team is fairly strong