Why are there so many people with metal detectors at crowded beaches?

Chances are that if you're at a very touristy beach, you'll find at least one person with an expensive metal detector kit spending their day scanning the ground.

What are they expecting to find?

A few coins or earrings, probably a couple dollars worth?
The whole thing is probably way more expensive to bring in the plane than the money they'll make.

An historical artifact? Really? In a super crowded touristy beach where thousands came before you?

Seriously, I cannot understand this hobby, can someone enlighten me?
Why are there so many people with metal detectors at crowded beaches?
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+1 y
It calles my attention mainly in places I've been to like yhe Caribbean or the Mediterranean, where bringing that sort of equipment costs a fortune
Why are there so many people with metal detectors at crowded beaches?
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