Harry the Hucker is a seller of souvenirs related to Sonic, even if a lot of them are a bit of a con job (like chewing gum that Sonic has used). He only appeared as a major role in "The Mystery of the Missing Hi-Tops", then made a cameo at Sonic's party.
He even went so far as to sneak into Sonic's hotel room and steal his sneakers in hopes to chop them up and sell the pieces as souvenirs. Sonic had him arrested. Even though things didn't end well between Sonic and Harry, he still attended Sonic's birthday party.