And they're not as comparable since game progression isn't "sped up" by putting money into the machine.
Also, with those, your paying for a random chance of more valuable products that, in addition to using in play, you can resell for cash. It's quite a bit more like gambling with and for money than lootboxes are.
Some people consider it gambling because you are preying on the same tendencies in people for your own gain. People also don't get any real value for their "gambling". Other people say this makes it not gambling, etc. That's a very simple oversimplification of the subject - there's a lot of articles out there about it right now.
The counter-argument goes that people "should know" and be responsible with their money, but I'm not a fan of that argument. It relies on people being perfectly rational actors that they just aren't.
I'm personally in favor of instituting regulation for these things. Even if it is just purely from the "we have to protect the children" angle - children are arguably the main market for these strategies after all.