It was an art piece so he wanted it to be more visible

I'd rather lug 30-40 lbs. of equipment around in a little wagon.

You say that like there's something wrong with a wagon.

I assume Google detects if you're walking with your phone, so that walking people don't mess up the traffic jam feature. And that dolley tricks these phones into thinking they're in a car.

I'll take a wild guess that he maybe wanted to build distance between himself and the phones, especially if he does this repeatedly. For a few phones, radiation and tissue heating is not an important consideration but for 100 phones it might be.

we will wait for your assertion to prove itself, then, together.