He replied and has blacklisted. Wished he would unvote though so our flags can take greater effect.
Scammers not making ROI'ing on a single post is a weak deterrent in my opinion. The consequences are not great enough. Their rep taking a hit would really make the sort of impact we need and also deter others due to the increased risk.
I've made it a policy to flag each @postpromoter comment on posts like this (unless they are unvoted) but may go a step further and flag the comments with rewards as I do not think the bot should be rewarded for tolerating their voting power be used to facilitate abuse. Quite the contrary.
I will do the same for any other bot I find complicit with this sort of thing. Blacklist is not enough. Scammers like this are gaining ground every day.