I've done that on a number of occasions. No effect.

One example: there's someone selling a short set of Tangiers chips from "Casino," and I've been looking for those for some time. The chips usually go for around $15-$20/set, but they want $11.95 for FedEx shipping.

I wrote to them and said that if they'd ship a less expensive way, I'd bid. Their response was "we ship everything FedEx only."

I still don't have the chips, and won't, when shipping equals the value of the lot.

Michael