I think someone from the US wrote about claiming the taxes back when they went. It might be in a trip report. Think Disney counts al there shops as one so can put all the receipts in.
The receipts need to be validated first at Disney, who then give a form which is scanned at Transport hub, i.e. airport, port etc.
I just did a day trip to France and went to Cite Europe in Calais, so easy to process. Just took receipt & passport to customer service desk. Who took the details and printed form out for me. I scanned that at Eurotunnel terminal and 2 weeks later refund was back on my credit card.
As mentioned whatever is being claimed needs to be in original condition. if its food related then it can't be consumed until out of the country, we went to hypermarket.