For
It helps people appreciate and learn about nature.
Against
It damages ecosystems and removes natural beauty for others.
Anonymous excerpts, translated where noted.
“A few years ago I decided to collect one stone from every place I visit; the result is in the picture.”
“If you enjoy collecting and respect the places you visit there is no harm in taking a few.”
“Legally, you cannot take them even from the river if you do not have authorization.”
“when a million people take a rock or two that's millions of rocks gone in no time.”