I would just start working the same way they do. If you’re the only one with that work ethic and picking up their slack you’re probably enabling them to be lazy because they know it will get done. If things stop getting done in a timely manner someone higher up may notice and do something about it then hopefully everyone will have to start contributing again. Also might be worth talking to your boss about it.
I’m not sure how common this situation is, but I’d assume different places have different work cultures. Looking for another job is a good idea, hopefully you’ll find a place that’s a better fit.