I must defer to the GRITS
I read this today and can't decide if I am more impressed by the nerve it took to do this, or repulsed by the sentiment behind it.

From Dear Abby's column on August 17, 2007

DEAR ABBY: My husband and I received a wedding invitation from my nephew's son, whom we have never gotten to know very well. Included in the invitation was a deposit slip to a bank savings account "in lieu of gifts"!
We later learned that everyone on the guest list received a deposit slip, even the grandmother. Is this proper? This is the first time we have ever heard of this, and frankly, we were rather insulted. -- PUZZLED IN COLORADO

I don't think a "How nice for you!" covers this one.

They clearly didn't think this through. I certainly wouldn't shred that deposit slip before throwing it out. In fact, I might feel compelled to tape it to the wall of a public restroom at Union Station or FedEx Field.