Some people need ear plugs all the time because they need it quiet when they sleep. Others can do with a bit of noise, even the a/c going on and off.
But being woken up at 3 a.m. in a motel room because of loud talking and laughing in a nearby room, that goes on for over an hour, is not a fun experience. So reported friends of ours.
I just checked my travel kit bag which I never unpack .... found it already has two pairs of ear plugs in it. We are good to go!