If you bought them new I'm guessing they ran close to 5 bills. I'd think for that kind of bling there would be some support included. Rattle their cage a bit, maybe they've run into this issue before.

Raggs is right, hotter plugs are intended to combat oil fouling. Running too rich can thin the oil on the cylinder walls and can score the cylinder walls or wear rings prematurely.

I'd rather give someone a tool than a solution. Give them an answer and they'll always expect it. Teach them how to find the answers for themselves and they will spend a lifetime learning.
As for my mental state?
"Not User Friendly"