That's incorrect. REST has no such restrictions on URLs. URLs can be completely random numbers with no human-discernible meaning.
REST is about architecture, about where state should live, how long it should live, how messages between entities should designate resources/state, all so you can preserve encapsulation and maximal flexibility for service upgrade. Your service is not RESTful if you don't meet these criteria.
RPC has no such restrictions, which means you're free to do everything wrong, which virtually everyone does, and you'll still be doing RPC correctly.
REST is about architecture, about where state should live, how long it should live, how messages between entities should designate resources/state, all so you can preserve encapsulation and maximal flexibility for service upgrade. Your service is not RESTful if you don't meet these criteria.
RPC has no such restrictions, which means you're free to do everything wrong, which virtually everyone does, and you'll still be doing RPC correctly.