You may have noticed an issue with a couple of game demos if you own an Xbox One, the demo for Fifa 14 and UFC were actually charging you to get them and play them, this has apparently been due to a technical error that has temporarily caused problems for the demos on EA's side. As such EA has issued the following statement:
“The price associated with the FIFA 14 and EA Sports UFC demos was due to a technical error. Both demos have now been fixed in the Microsoft store.”
You can now rest assured that if you really want to play the demos for these games you will not be charged so have fun on the Microsoft Store. From my understanding this has only happened on the Xbox One and no other versions of the demo were affected.