Eric, you've done an amazing job of staying polite and cool on this thread. Thanks!
I drove south to Nevada 2 years ago to buy my DW's pre-owned vehicle. I didn't pay any Nevada-specific taxes or fees, but was very prepared to pay the sales tax for here in Utah when I went to register it.
OTOH, I have a friend in California who used to store his ski boat across the river in AZ for two reasons. 1 - Only needed to tow it to the launch ramp a few miles away. 2 - Much lower registration fees. #2 started the whole deal. He probably paid more in storage rental than he saved on registration, but his gas savings probably made it closer to a break-even proposition.