I have been rewiring the garage, and running in to all sorts of crazy
wiring. But here is something I have never seen befo a normal brown
outlet with the normal 4 screws (2 hot, 2 neutral), but with TWO green
ground screws, on either side. I assume this is/was to make it easy to
just wire incoming ground to one screw, then outgoing ground to the
other, without need for a pigtail. Or same if it were (at the end of) a
split circuit with two incoming cables.

This doesn't sound entirely kosher to me: I thought the ground path was
not supposed to rely on a device, such as an outlet. Is this just
outdated, or is there some other reason for it?

Thanks,
Kevin

BTW - my favorite oddity in the garage (this one just silly). A part of
the circuit was connected to the rest through a male + female plug
installed into the middle of a cable. Even though both sides of the
cable had a ground, and they had a 3-prong female plug, apparently they
could only get a 2 prong male side. So they sawed off the ground prong.
Then, to top it off, they immediately put the plug in upside down in
the socket, to get swapped hot on the downstream circuit.