I don't think anyone was trying to represent that the stuff wasn't worthless to the person posting. In fact, I think that it was clearly stated that the stuff WAS worthless to the person, hence why he's dumping it for free to anyone that wants it.
And, I'll agree with you - many curb alerts ARE things that we don't want to take to the dump.
My personal story:
A couple years ago, a business venture left me with a bunch of CRT monitors. 17", 19" and 21" all working great. After I outfitted myself with a couple of choice 21" monitors, I tested rest, verified they were good, and ensured they were bundled with a VGA cable and a power cable. It really wasn't worth my time to sell them for $10-$20 each, because LCDs had been coming down in price significantly, and these were heavy boat-anchors.
It was a nice sunny weekend. I set them up on some folding tables I have, took some pictures, and I posted them on Craigslist for free - size/make/model described on all of them, condition noted on all of them (even going so far as to detail the amount of "fade" the stuff had (y'know, when gray plastic begins to yellow?) and noted that you could take one, take them all, I don't care, come and get them, first come, first serve. I was besieged with all kinds of calls and emails, wanting me to hold them for days/weeks, wanting me to deliver them, etc.
It was, quite frankly, a giant pain in my ***, and NOT worth my time to deal with.
Such a pain in my *** that this past summer, when I converted my final display over to LCD, and had another pile of good, working CRTs available, instead of offering them on Craigslist, and after calling the local school district, who didn't want them, I took them to the local dump's recycling station, because I wasn't going to screw around with the nonsense from Craigslist again.
I'm sorry, but I don't think that it's rude or discourteous to NOT want to deal with people that have unreasonable expectations of free stuff. Those people are the ones who ruin it for the reasonable people that I would have liked to have given the usable stuff to.
If someone's time is so valuable that they can't risk "wasting" it in the pursuit of free stuff, then perhaps they shouldn't be looking for free stuff, and instead, just go buy it.