I have people follow me to my car at the grocery store when they notice I'm in a good spot (there are other, less desirable spots available, mind you). I take my sweet time loading my bags make sure nothing will tip over in transit. And during the time I'm loading, sometimes I decide I need something from the adjacent liquor store.
I've never understood why people sit and wait for spots when there's spots available. Drive around. If someone is pulling out, sure, but don't watch people load their shit up.
Yeah, I don't sit and block traffic because I'm too lazy to find another spot. "Do unto others," you know? I don't like being made to move faster because you just need this spot.
EDIT: And hold up, you'll move your car and load it? So you will leave your groceries just in a cart, go and move your car to some further spot, and load it there? How is that at all the right thing to do? Where are you moving your car to, an empty spot? Like, one the person who's sitting there waiting could've parked their car?