I originally had 3 rocks around the player, to almost force a bump into one. However, it seemed too much and didn't look right. After changing it to one rock and one tile away, I was doubting that players would accidentally run into it. From the comments I can see some players didn't realize you could move rocks from the start, and some did (which I assume could be accidentally hitting the placed one, but could also have been just seeing the gun and wanting the item). All that said, it's good to know that design decision helped someone.
Thanks for playing!