Granted almost half the time I've posted images it has been to troll or make fun of something, but the other half have been screenshots, charts, and legitimate on-topic images.
These forums don't need to become 4chan just to allow photos, and what kind of an admin can't restrict sizes?
I say we charge for photos and that will shut everyone up.
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Disabling features doesn't keep people from anything but productive communication. Try limiting who posts them instead.