One could go to the offending person's wall and mute them. The mute button is right by the follow button on everyone's wall.
There are no rules about spamming or not spamming people, but to me it is like dogs taking a crap on your living room floor. Thus I mute and don't have to bother with them again.
Community
Is there an Etiquette Guide for Steemit?
There are no official rules for participating on Steemit.com, but one of the users has created an Etiquette Guide for the community. While it is not required to follow the suggestions in the guide, they are standards that many users in the community choose to follow.
Souce Steemit FAQ's
https://steemit.com/faq.html#What_is_Steemit_com
I would be very careful about this as there is an unwritten rule.
"Harm No One"
Question: Are spammers "one"
Answer: Yes
To me steemit is a anarchy community which means you have to take care of yourself and that is why they supply you with a mute button. Thinking that someone should come and protect you (as mommy and or daddy) isn't part of the anarchy social cultural tradition.
RE: The WAR against Spammers Rages on !!! HolySmoke! ... losses on both sides !!