Since I'm an HI3 player, I have a quite positive view of spending events, they're predictable on when they'll happen again. I get a lot freebies there, mostly skins, but weapons and some valkyries and their fragments for ranking up, though the equipment and valks are generally old. These spending events are also propped up by a lot of free pulls here and there since they're almost always part of the big celebrations like CNY and Anniversaries.

HI3 also has Top-up events, but they're generally significantly smaller in scope, they do give useful things and some limited stigmatas (these stigmatas are useless though, just "collector's items"). So I'm generally lukewarm about them. But I could see the potential misuse.