Using UPSes

I know that using UPSes in servers environment is a MUST and it prevents many problems, but what about workstations and other network equipment [for example switches]?

If we ignore the idea that UPSes can [and most of the time do] save some hardware during power failures and assume that we use UPSes just to keep servers running 24/7 no matter what is going on, that why do we need it if lets say switches are not backed up with UPSes? On the other hand, why do we need those switches if all the workstations are not on UPSes as well?

And the main questions are: \”Is it worthy to move all equipment on UPSes?\” and \”What kind of setup is better?\”