"It's somewhat odd that grey heatshields seem to be the premium member of Patriot's new memory lineup, with 32 GB kits and high-speed DDR4-3200 available only with grey aluminum heatsinks."
I think you missed the actual marketing trickery roadmap there. Patriot knows enthusiasts will go for 32GB+ of RAM. Nowadays there is quite a large crowd sitting in between 32GB - 64GB, but 32GB is much more common. Usually those enthusiasts care about how the system looks and try to match design language and colors. Blue, White, Black, Red are very used. If an enthusiast wants DDR4 for his / her Intel platform, he /she will want to match some colors - hence blue (or any color other than grey) is not available EXACTLY for the 32GB kit, which will force some into (at least) considering the 64GB offering.
If I were to do so, I would consider another company's product. Period.
Somebody who hunts down for people like that to suck money like a vampire sucks blood has a very clear definition in the dictionary, which is a word starting with c and ending with unt. You may realize these heatsinks are identical except the paint on them. It couldn't be more obvious there's no supply issue or shortage in the mix since they can easily manufacture all kits with all colors available, but deliberately decided not to.
Also to be considered is the color they limited the 32GB kit with: grey - it expresses a clear will to remain in the unknown, in the anonymity, to be perceived as invisible by the rest - it's the main color to use if you want NOT to stand out - oh WOW, HEY isn't that the exact opposite of what most high-end system builders want?
It makes perfect sense.