A 3 way or 4 way switch can be used as a standard on/off switch ( as a regular switch on the circuit) , just waste of money and cost.thats a fools errand....
3 way as regular switch if he used that dark screw and either one of the traveler screw to switch only the hot with like a regular switch.
4 way switch is same except he uses 1 of the two from one end and one of the two from the other end . As on/off only regular switch. Switch wise it will absolutely work. Dunno why you wanted to.