Bill,
Good observation...
I have seen that time and time again. Something you also really have to watch on E-Bay is the shipping costs....many sellers avert or mitigate the risk of something being sold at too low a price by building in a comfortable "pad" in the shipping - it's unethical. Many times they don't even list the shipping price for this reason hoping to sting you after the sale.
I've negotiated this with sellers more than a few times - and got them to reduce ridiculous prices on shipping.
I'm willing to pay the person for the time, effort and materials of the packaging, to include postage, but when shipping a small part is $25-30, and it does not even include insurance, then I pass or negotiate.
MM
