Oilfield stickers and hard hat stickers are almost as good as currency in the oilfield. Hell, they could even be considered a right of passage.
It's easy to point out a worm with his clean hard hat and no stickers. But the longer you're in the field, the more oilfield stickers you accumulate, and you see the grease and oil bake into the glue on the edges.
Most oilfield stickers are company names, freebies you get when service hands come out to the rig. But our oilfield hard hat stickers, they're funny, outrageous, and might even piss off a snowflake.