Between covered pickups and open coil pickups?

I'm just watching one of Eric Clapton's live recordings and he has covered pickups. And i'm just wondering, Is it just for looks or what?
Not really much difference in sound if your comparing it to the same pickup that's open coil.
Schecter C-1 Elite
Gretsch 5120
Fender Ultra-Chorus Amp
probably is more for cosmetic reasons than anthyhing else. Could also possibly help protect the pickup?
SG commando

Inserts hilarious quote here
As far as I know it's purely aesthetic.

But it does look pretty cool if you go all "Jimmy Page" on your guitar's ass and take the cover off the bridge pickup
They didnt change the sound of my guitar at all. If youre gonna get
some...be different and get them engraved. Basically go to a trophy
shop or one of those picture frame stores for grandma's and get
anything u want for under $25 for the whole set.
I bet Charlie Brown's teacher's name was Mrs.Hammett
i think its just to look cool or something
"It's not about who has the biggest stick, it's about how hard you can swing it"
Well you could be talking about lace sensors. They completley change the sound. They are much hotter than regular single coils, however I much prefer single coils.
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