I agree with you and like your opinion "And why would anyone take it upon themselves to change the message instead of passing on exactly what he heard? I guess it is human nature to add our two cents, to think that we know better." I hadn't thought of that angle.
It only took one of the kids to really changed the message for it to almost change completely.
I am finding another element of poor communication. As an older person, I'm finding fewer people pay attention to what I say and seem to look past me when it's my turn for customer service. It's been interesting and unexpected.