I don't think I can stomach reading this entire thread, but in case someone hasn't already posted this:
Section 9 (limits on Congress), Article 1 include a prohibition on Bills of Attainder:
"No Bill of Attainder or ex post facto Law shall be passed."
And the Contracts Clause in Section 10 includes:
"No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal; coin Money; emit Bills of Credit; make any Thing but gold and silver Coin a Tender in Payment of Debts; pass any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or grant any Title of Nobility."
Singling out certain employers after Congress has already made welfare and food stamps widely available violates the Constitution, imo.