Why not go with all HRs? I don't see any advantage to having plain receivers. I do understand if it's monetary considerations.
Yes, it is primarily monetary. Not everyone has the ability to throw hundreds of dollars at equipment. I have about $500/month in recurring medical costs for my wife and I. That's where my disposable income goes.
Also, I haven't watched TV in the dining room or the office in weeks. The dining room table is a catch all and we go months at a time where we don't even eat in there and when I put the TV on in the office I listen more than I look since I am probably working.
The third legacy receiver which is in the kitchen is on on while I am cooking dinner or while my wife and I are eating. While I am cooking I am listening more than I am looking and while we are eating the 19" TV is on the other side of the room...far enough away from our "old" eyes to make it a moot point.