It's common nowadays to wear something in or over your ears to listen to music, a podcast or talk on the phone. Some people use them for hours on end every single day.
Headphones don't go directly into a user's ear, but that doesn't make them exempt from dirtiness, especially the ear pads.
Supermodel Noami Campbell is said to be into it, as is the US military. Here’s what you need to know about ear seeding.