OP, you are spot on, most here have no clue.

Additionally when you sell something at a profit you get to pay taxes! yay!

When I borrow against myself I pay NO taxes.... Oh boo  I know.

I  do it against my 401k all the time,  say I want a new truck. Borrow against my 401k, guess where the interest I do pay on it goes? TO ME! win-win.

Down side is it does nothing to build a credit rating. Okay, wait to the end of the year and snag a zero percent auto loan for the Mrs.... boom.