Laboratories of democracy. The problem is the "substantial effects" doctrine of the Commerce Clause has muddled what started out as a clearly enumerated power into an open-ended usurpation that has no objectively discernible limit.
But think what all those bad rulings could do in a Constitutionalist’s hands. If every human action is “in commerce”, then every government action must be. How many local, county and state zoning, licensing and permitting ordinances are restraints on trade or limitations on the 50 state free market America is supposed to be. It’s a very sharp blade that cuts both ways if we let it.