The Episcopalians may not take too kindly to your insinuation that they are too lazy to develop their own theology so they poached what they liked of ours. 

Your argument boils down to: the Episcopalians wanted to be more like us so now we should change ourselves to something different. 

To make up for that we should steal something from the Episcopalians.

That is either a silly argument and/or you really hate Episcopalians.