Yeah. Some of the green tiles in dungeons are secret switches that open holes in walls, make buttons appear, open chests or do other things, and when you step on one, a footprint appears on it. Since the chests are opened with these tiles I thought it would be cool for the seal on the chest to not be a lock, but to have the same design. The one on the tile in the ceiling is only there for decoration--you can't walk on ceilings, after all.