$109 for your 1 day / 2 parks? The french site offers me the same for $71.60.
I think you are comparing prices of different tickes - the SUPER MAGIC ticket (which is valid any day of the year) for 1 day/2 parks is USD 109 on the US site and EUR 80 on the French site - which is the equivalent to about USD 95, not 71.60. The ticket that would correspond to USD 71.60 is the MINI and has many blackout days (most weekends and all days from 4 July thru 23 August plus most French school holidays). I don't think the MINI ticket is available on the US website.
I am also not sure if it will work to use a (fake or real) address in France, as often the problem lies not in the mailing address but in the billing address attached used with the the credit card - if you are unable to change the country on the billing address, the transaction usually fails because the billing address cannot be correctly entered.