Because the grocery stores know they are doing something illegal by selling bad twinkies its only a matter of time before they get shut down. SEC's standards were put in place to protect the investors and any stock exchange service should comply if operating within its jurisdiction.
Side note: would it not be possible to create a p2p exchange program?
I don't think it should be illegal to buy bad twinkies. I don't think investors should be "protected" from buying stocks that the SEC doesn't approve.
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I know what you mean -- if we don't speak up for our right to bear Twinkies, they'll take away our rotten beef rights next, and when they come for our salmonella-infested poultry, there'l be no one left to speak up

(Twinkies?)