Ok, best I ever did was sending someone to the home center for “Checkerboard Paint.” With any really really good concept for a joke in someone being suspicious of it’s concept - you have to have ready a good explination of how it works. Sure, you can even these days buy some form of board stretcher, but imagine if you have in
stock the expiation of how checker board paint works for that joke. You joking with me? No, this is how it works... It’s all about the ionization of particles, think about ionizing sun-glasses. They work due to the amount of light ambient. This paint works in the same way in electrons
lining up one way or another. (Distraction in explination is the best way of making one’s case for how something else works.)
Yep, worked well and given recent spray paint developments might not work as well but still as a concept there is no checker board paint available. Not possible, but if you describe the science behind it sufficiently... seems feasable. Just got to confuse with useless unrelated science and leave out the details of how to make like 1.5" squares in detail. Details replaced with say how ions align and separate to the poles in sun glasse aligning as a distraction. Story good, science good = shopped for and one can believe it was probably more than one home center person confused. Confused by the science understood by the shopper fully (possibly some acting training to make it seem real in science and that need for it on a project.) Home center people added fair game in if you make the science real enough to the shopper... they will also fall for it in nope not having it but trying to help the customer find it.
Best
level of joke you can go for is in capturing not just a shopper for it - just special order it already... If you have convinced the buyer about the science in ions
lining up sufficiently, they will sell your product sufficiently in buyer to sell most sales staff. This sufficient to sent it up to corporate to get by X date from corporate.
That’s a win win situation in if it don’t exist, nobody hurt or perhaps more educated in the end. Done that.