Gerhardt's Law Strikes Again... and Again

A couple months ago I elaborated on Gerhardt's Law ("If you find something you like, buy a lifetime supply because they will stop making it.") and its many applications to my life. Since then, it hasn't gone away. Oh, no, Gerhardt's Law is alive and well, and it has my name all over it. To wit:

1. One of the previous examples I gave of things I liked that succumbed to the Law was "Mazola 100% corn oil margarine. Fleischmann's 100% corn oil margarine." (I guess maybe that's two things.) Well, apparently I can now extend that to include Kroger's 100% corn oil margarine. It was the only corn oil margarine I had been able to find in this area, and it was only a buck a pound. I don't buy much at Kroger's, but I did drop in every so often and pick up half a dozen pounds and put them in the freezer. So today, finding myself down to my last half-pound, I went to Kroger's. And found only soybean oil margarine (tagged as "NEW!") with a Kroger label. No sign of the corn oil "Churn Gold" stuff, and no empty slot in the cooler where it should be. Crap. Soybean oil margarine... well, to put it delicately, it doesn't agree with my digestion.
2. Unlike the ill-fated New Coke, I actually liked Coke C2. It didn't taste exactly like Classic Coke, but I liked it OK, especially if I drank only C2 so I wasn't constantly comparing the two. At half the calories, it was a nice compromise for someone like me who hates Diet Coke. So of course, it has now apparently disappeared from the local market. I haven't heard anything specific about it being discontinued, but my suspicion is that it's being replaced by Coke Zero (which I tried and I don't like).

The only question I have is this: How the hell do they always know what I like, so they can stop making it?