Earplugs for me are a necessary item. Very rarely am I in a sleeping situation where it is quiet. The romantic ideal is that we sleep in pristine nature with crickets and night creatures soothing us to sleep. That does happen but not very often on the type of touring I do. Highway noise near a stealth camp spot, campgrounds with sites too close together, generators and even hotels have hallway conversations, door slams etc… A simple set of earplugs makes it all go away. I have also given them to others who I know will be sleeping nearby me because I know that I can snore like a chainsaw.
My go to earplugs are made for industrial situations. They are made by 3M and are very comfortable. Some plugs are too dense and after a bit I feel like my ears are sweating on the inside of them. These block out a great deal of noise but let in some louder sounds. It is hard to explain, but like the door slam example, you hear it but it is not so jarring or intrusive.
I buy these by the commercial box of 200 as I also use them in my shop but they are available in smaller quantity as well.