Yeah, "They just sprout up out of the ground" as my riding bud says.

About a year ago my bud and I were riding homeward after dark. I accidentally dislodged my frame pump as I reached for my downtube shifter on my road bike. Luckily, the pump fell to the ground and missed all the moving parts of my bike as we were doing near 25mph at the time. So I yell up to my bud that I dropped something, swung a U-turn and went back to look for it. I could not find it because two dudes that "sprung up out of the ground" had already picked it up. My bud saw them holding it and told them it was mine. They offered to sell it back to him. Just then I was returning from looking farther up the road. My bud snatched it from the guy's hand and instantly handed it off to me like a relay baton. Then he sprinted away from them. Luckily, no guns were involved.

I would have let then keep the pump. Might have suggested exactly where they should keep it too.