Yeah. I don't know the details and I very rarely see them in stores. But there's some sort of system that, as parent says, basically immediately locks the funds so (as I understand it), there's no risk to the store.

I assume things like car dealerships use the system as well. When I bought a car recently I just gave them a personal check which they were fine with. In the past I had to go to my bank and get a cashier's check.

You don't even generally see signs about returned check fees these days.

They're not super-common in general for most use cases but they're still the most straightforward way to make personal payments (other than in-person cash payments) without going through some process that's more involved than giving someone a piece of paper.