Going to disney in less than a week...!! Wondering, how much cash do you really use?? You can use have your room key as a credit card, right?? Do all of the vendors (popcorn, soda/pop, mickey bars, etc.) take that type of payment?? What about Disney Dollars?? Can you buy disney dollars once you get to Disney?? Do the vendors accept Disney dollars...or do they only accept regular u.s. currency? We don't want to take more cash than necessary...we're credit card type people. Any info you can share would be appreciated! Thanks!!