Yes, you can report a possible over-inflated shipping charge. eBay will investigate and pull the auctions if necessary.
I have had the calculator mess up on my auctions before. It was charging about $20-25 more than typical to ship a Lee Middleton doll. It ended up that I had to add a note to my auction stating not to use the calculator and quoting a flat rate for shipping. I had five auctions up at the time and ended up losing a dollar or two on two of them with the flat rate.
Additionally, I have used a very pricey mailing store to send American Girl dolls. Well packed, as they insist on 4" of padding around all sides, it cost $11-12 (that's UPS fees and the pacing service, I provided the boxes) to send a one doll from Michigan to southern California. It was only slightly less to send to nearby states. I sold 7 dolls around that time.
Something's amiss, either the calculator or the person's calculations, so I'd report it. It may be a scam, or it may be an honest mistake. Either way, I'd do my best to help eBay know about it so they can check it out.

<font color="#33CCCC" size="1">[ August 05, 2006 11:06 AM: Message edited by: jrtmom3274 ]</font>