If you have AR and don't want anyone to drop seeds in your town, this code can check each player's inventory for seeds when they enter, and then check each players text for seed codes (anything over 5000 except FFF1)
I already have each wi-fi players text address, and you can even make it only check visitors so it won't bother you. However I'm not sure what it should do if it does detect a seeder (should it go into an infinite loop and freeze? Or should it put something on their text "I'm trying to seed you, power off!" XD)