Credit Card Fees on Foreign Travel

Should it be legal for credit cards to charge fees just for using your credit card when traveling abroad? I understand that they get a markup on the currency exchange.. and even though I don't like that, I understand.. but then to charge an additional fee on top of that... I think it's criminal! Does anyone else agree?
I found some pretty good ideas and strategies on how to avoid these fees on the 'captain's lounge' forum at http://www.thetravelsteals.com that I'm going to try and impliment, but I think these fees should be eliminated! You should also check out The Travel Steals 's deals on luxury all inclusive travel packages. They are the best prices I have found online.