Posted By:
JimBJay,
Sure they are not rare when compared with a number of other vintage cards and sets. The Wagner isn't either for that matter. But when one matches supply with demand, they both become hard to find and valuable. I think it would be hard to argue that the T206 set is not the most popular pre-WWII set. I think the only one that approaches its popularity in terms of numbers of collectors is probably the 33 Goudey set.
JimB