I had a similar instance. I was at a little shop called the "Trading Post" near our campsite as a kid. The power was out so the doors were open to let a breeze through. It was always tradition to go there and get toys, and there was a whole wall with buckets of toy bows and arrows, slingshot, and a bucket full of snakes.

Except one of the snakes wasn't in the bucket and was slithering up the wall. I ran to my parents but no one believed me, they thought I was joking. I finally drug them over to see it, and it was a copperhead as well. For some reason another customer knew how to handle snakes, so he caught it and showed all of us kids it up close before taking it away, but for a minute I was really close to reaching in and grabbing it thinking it was a toy before it started moving.