Used earbuds are kinda gross, it’s his wife but still…
Are you, like, buying a new spoon every time you want to eat? Are you unfamiliar with the concept of cleaning?
In their defense, properly cleaning headphones is kinda hard, especially wireless earbuds.
Source : Used to work at an electronics repair shop that cleaned stuff, and even clean ‘looking’ (aka externally clean) headphones can have some disgusting junk on the inside.
But the outside part covers the inside and is the only part that goes inside. The inside is still inside while being inside your ear protecting the inside of your ear from the inside of the earbud.