Why do so many sellers take offense to offers on their listings?

If you have the 'offer' feature activated then what's the problem with any offer. Comments like 'lowball' offers will be ignored just gives me a bad vibe. If your item has been up for sale then there is no insulting offer. I've made deals with people starting far apart and coming together. If you haven't noticed the audio market seems to have come to a standstill. Any opinions?