Haven't read every response so might be repeating something already said here.
Should add another option to the poll of "I buy crates sometimes and don't consider them to be gambling".
To me gambling would imply a risk of losing money and gaining nothing in return. With crates sure I might get 4 items I didn't want or that I just exchange for gems but I am still getting something for the money spent.
Would I rather just pay directly for specific items? Yeah, but I still want them so if I have some crowns I go ahead and try for it. Worst case scenario I gradually save up the gems/seals for it and get it in the future.
If I could change one thing, and one thing only, about crates I'd make it so you can exchange anything and everything for gems. I've got a few mounts and cosmetics that I know I'll never use so it would be nice to be able to instead get gems to put towards the stuff I do want.
So I've mentioned it before, but just because you don't mind spending money and getting random things in return, doesn't mean it isn't gambling.
Globally/Universally (Outside of preference and opinions) = Crates are gambling.
One person may be buying crates with hopes to win a Skin. If they get a hat they didn't want/need, it doesn't change that they gambled for the item they did want.