Because you are slandering my name? Because when buyers see scammer next to a name they lose a certain amount of confidence? If you do not understand this then you should probably finish your high school business course.
I'm not calling you a scammer.
Bitcoin is still a small community. Two newly registered people selling the same products, the first who conveniently deleted their first listing.
Similar posting times, posting styles, and your account has less time spent online than the first one, which can indicate that you're not completely new.
Is it proof? No. It's why it's a warning.