Questions about Shovelware

I never even thought about devs making money on cards, I suppose they probably do get some small cut.

Even the worst games will get some sales, doesn't take that many to make their money back is my understanding.

With youtubes intentionally playing bad games often, that's near guaranteed sales, making it especially bad might even help this.

How are these shovelware games on steam making any money?

They mostly make money off steam. Use bought assets, make a game in a week, sell 1000 keys to a bundle site for $300 and move on to the next project.

They make money from Trading Cards, that's why most end up giving away tens of thousands of copies, then they get a cut for each trading card sold on the Steam market

The card sales was the major one I was thinking. The selling of keys to bundle sites was another I hadn't thought of.