Nah nah, the shovels show up at several pois, you dont actually need it though. It's just kinda flavor, like the break action shotgun showing up everywhere.

The one with samples in the ground, I think I've only ever seen one per map at most, but you'll see a little clearing with a shovel somewhere nearby. If you walk into the clearing you can see the samples in the ground. But like I said, you can just lay down on the ground to reach them, you don't actually have to dig :)