Ignorance and vapidity.
"Strict Constructionists" do NOT apply the IntStComm clause to backyard vegetable/home consumption businesses.
Scalia may want to reconsider his respect for stare decisis in the light of the eminent domain case (esp. after CFR).
Of course, a ruling restricting the commerce clause to its original meaning might in effect be a full-employment-for-lawyers bill: wouldn't about 87% of things (for want of a better word) be "ripe" for a new try?