My 2 cents :
I think it's just like insurance. How much faith do u have w/ BMW? Even mb suv had problems when the 1st ml came out! & in case ur car turns into a lemon asa the warranty xpires.
In the current business environment, they can stop taking new policies or increase the price anytime.
The wheel & tire policy is a must because u dont know what's on the road around a blind corner. Or whether some construction vehicle left a bunch of rusty nails on the road.
I'm sure even the 19" tires are at least $300 each b4 labor. And would u just replace one? U may have to buy 3 other new ones to match, while the tire warranty replaces only1. If a wheel is damaged that's even more $$.