According to the FCC's rules that govern toll free phone numbers, you are not allowed to hoard numbers in order to sell them for profits.
If you have a bundle of toll free phone numbers (that you specifically obtained because of your preference for certain combinations of digits) and you are trying to auction these numbers off to the highest bidder, with the starting price adjusted based on your personal appraisal of the value of the combination of digits; then YES - THAT IS A CRIME AND THE PENALTIES ARE STIFF.
In fact the penalties could reach as far as into the buyers of the auction whose toll free numbers could be revoked by the FCC and SMS/800 since it was purchased through an illegal means.
Of course all of this is up in the air until the courts have a trial.
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