EXAMPLE: Frank operates a fireworks store in Southernstate. The fireworks he purchases from his suppliers are made entirely within Southernstate from materials found locally in the state. Despite the modern trend toward even the smallest of shop owners selling online across state lines, Frank sells only from his storefront. In other words, everything Frank does is intrastate. In an effort to end the increasingly heated price war among fireworks retailers, Congress passes a law establishing minimum prices for fireworks. Frank is fined for violating the law, and defends himself claiming the law exceeds Congress constitutional powers as the activity regulated is entirely intrastate.
What would be the result in the Franks Fireworks case above? The view taken by the Court today would be that Congress is fully within the bounds of the Commerce Clause.
There was a time, however, after Gibbons and the Shreveport Rate Cases, when the outcome would have been otherwise. In Schechter Poultry Corp. V. U.S.,295 U.S. 495 (1935) and Carter v. Carter Coal Co., 298 U.S. 238 (1936) the Court struck down acts of Congress refusing to find support in the Commerce Clause. In 1937, however, the Court decided NLRB v. Jones & Laughlin Steel Corp, 301 U.S. 1, and between 1937 and 1995 the Court did not strike down a single federal statute as exceeding the powers granted Congress in the Commerce Clause.
http://nationalparalegal.edu/conLawCrimProc_Public/CongressionalPowers/SubstantialEffect.asp
This would seem to be in direct contradiction of your conspiracy theory.