Even if this idea wasn't against eBay's policies (which I'm sure it is), this would last for what, a handful of auctions before sellers stopped bothering with eBay?
If i sell something locally for $40 and I list it on eBay and get $37, the process is relatively worth it if I end up selling more stuff.
If I list it on eBay and it starts selling for $7 I will stop selling there.
Capitalism just sort of works itself out that way....lol.
-Ed