Anybody who routinely travels overseas needs some form of tech solution to local toll charges. Doesn't really matter what it is. Even if you don't sign up for a plan, Skype back to the USA can run as little as $0.01/minute or $2.99 "unlimited" for the month in which you are traveling.

Bottom line for OP is that he has two choices: 1) call Marriott; 2) lump it.