Many simply say there offer is not a chain letter. Promoters of illegal schemes love to misquote Title 18 of the United States Code on Mail Fraud. Usually sections 1302 and 1341. Judge for yourself. The actual text of relevant sections of Title 18 is printed below.
Chain letters are very tempting.
Most people at one time or another do try at least one. Your mail carrier will notice an increase in your mail volume that may be reported to the local Postmaster or to Postal Inspectors. Nothing may happen, or you may receive a warning, to cease at once. Whoever knowingly deposits in the mail or sends or delivers by mail. The Postal Service may ascertain the existence of the agency in any other legal way satisfactory to it.