Since we're talking about the ground, or EGC ....
As you can see in the earlier pictures, the kiosk appears to use a #4 bare copper wire, in PVC conduit. Here's the termination at the rod end:
How local practices differ! I would not have done it anything like that - as I am accustomed to running the EGC in EMT. Here's an example of how I expect a rod connection to appear:
(Picture was taken before hole was filled in).
I must admit that running a simple wire to an acorn sure does look a lot easier.
Some might have concerns about this ground rod being vulnerable to damage, or posing a trip hazard. To be fair, I don't see this as an issue; it's placed such that one is not likely to encounter it. The electrician was there probably before the plumber tore up the pavement ... though I agree it would have been better for the rod to be completely buried.
Regarding the lack of mushrooming on either rod pictured:
The kiosk's rod is in soil that allows for an exceptionally easy driving of the rod; there is very likely an entire 8-ft of rod there.
The other rod pictured was set in a dug hole, a hole used to place a pole, and backfilled. No 'driving' was necessary. Indeed, the rod is partly encased in the concrete of the post footing.