Maybe for rare arcade items you can be stricter, but I upgraded to the premier account years ago because I just felt the whole thing was a wash. Ebay's an auction site. The more bidders you have, the more likely your item is gonna sell for more money. I know when I'm bidding, if an auction doesn't accept PayPal, I just go to those who do. I realize this is different (still accepting PayPal), but I'm sure people who fund purchases with credit cards just go to auctions that do (Regardless of other payment methods). Remember, even if a credit card bidder doesn't win an auction, if they bid, they may have drove up the final purchase price. Just my two cents. Now if you're only selling rare items (so seller can't be picky) or fixed price items, it sucks for sure.
Edit: Just read the last couple posts and I have to agree. It seems around the time of my upgrade to Premier, I no longer charge actual shipping charges. If I'm shipping a Priority (Under 1 pound), I'll charge 5.00 shipping (Actual charge is 3.85). Don't think this matters much (Since people factor in shipping charge when setting their bid limit), but at least it's less money Ebay is charging commission on.