Sometime around Christmas, Sarah Burzio noticed that the holiday sales bump for her stationery business included some mysterious new customers: a flurry of orders from anonymous email addresses associated with Amazon.

Burzio, who doesn¡¯t sell her products on the retail giant¡¯s site, soon discovered that Amazon had duplicated her product listings and made purchases on behalf of Amazon customers under email addresses that read like gibberish followed by buyforme.amazon.

¡°I didn¡¯t worry about, it to be honest,¡± she said. ¡°We were getting customers.¡±