Whoever, at any sale of property held by the lawful authority of a public servant as such, purchases or bids for any property on account of any person, whether himself or any other, whom he knows to be under a legal incapacity to purchase that property at that sale, or bids for such property not intending to perform the obligations under which he lays himself by such bidding, shall be punished with imprisonment for a term which may extend to one month, or with fine which may extend to $1,000, or with both.