Self-service hotels/hotel chains around the world?

Not exactly like you've described, but close...

citizenM hotels use an automated check-in system. Upon arrival at the hotel you enter your details, swipe your credit card, and the system issues you with a keycard that gives you access to your room. You then use the same kiosks to checkout at the completion of your stay. At no point do you deal with a human.

Many hotel chains, including Hilton and Marriott hotels, also offer some form of e-checkin and digital key combination, normally using an app on your phone. This allows you to check-in from your phone, use your phone to open the room to your door, and then check-out using your their app - so again, no human interaction.

However in at least some cases these e-check-in/digital key systems will require you to visit the front desk, in particular to show ID (especially where required by law) and/or your credit card (especially if it's a card you haven't used at that chain before).

Many budgets hotels use safes/keyboxes, I've been to maybe 10 of them.

I've also been to one that used code locks instead.

Personally I prefer the code locks as I don't have to keep track of a key and I've nothing to do when checking out except for leaving the room.

One way of knowing if the hotels are using systems like this is to check the reception hours which aren't long, like 12:00-15:00 with check-in 24 hours means there's probably a system like this in-place.