Hate-Mail, anyone who's played online games for any length of time has probably received hate-mail at one time or another.
Mixed somewhere in all the ranting, raving, name calling and obscenities the hater usually mentions what he's so mad about. For market/auction related hate-mail it's usually something like:
"You're selling under cost!"
"You're paying too much for that item!"
"You undercut by too much!"
"You're killing the market!"
And the big lie...
"You'd make a lot more if you'd just undercut by 0.01 ISK like I do!"
That's what the no-lifers and bots want you to do because it means they make more ISK, not you. The guy telling you to undercut by 0.01 ISK is either naive enough to believe the no-lifers and bots or more likely he's one of them. He's pissed you entered what he considers "his" market(s). If you don't play the 0.01 ISK game he can't dominate the market, manipulating and price gouging his way to obscene profits by camping constantly anymore.
I used to get hate-mail almost daily from other auctioneers in that game I played before Eve. To my complete amazement I haven't received one single market related hatemail in Eve yet. I've gotten a few for running someone's gatecamp or making fun of his obvious scam in local chat but none over my market related actions.
I can't believe no hate has been sent over my market actions. The haters must think my characters are someone else's alts and send the hate to his main instead of me.