The reason some things have gone through the roof is at least partially attributable to the popularity of type collecting and back collecting vs. set collecting. With many of the same fronts on a lot of the caramel and T sets, and the high prices for commons, it's rather easy to see why type collecting and back collecting has taken off the way it has. As far as rarity of T208's, before these 2 new groups showed up, they were some of the more rare ones I had ever seen. We see this happen fairly frequently nowadays. A seemingly super rare card gets sold for a high price...then 20 (or more) pop out of the woods. "Everybodys" and "Holmes to Homes" M101-4/5's come to mind. I am just waiting for the next 30 T231's and Virginia Extra's to come out.....
here's a couple common W573's for perusal....