An elderly couple go to the doctors. When it is their turn, they enter the room and the doc asks them what he can do for them.
"Well, we'd like you to watch us have sex" says the woman.
"Ahh......okay" says the doctor hesitantly. So the couple jump on the bed and go for it. When they're finished, they say thank you and leave without any more comment.
This goes on for another few weeks, until finally, the doctors curiosity gets the better of him.
"Look you two, you both seem to be fit, i don't see anything wrong with the way ur doing it, and you haven't asked me any questions, so please.....why do you keep coming here?"

The woman replies "well doc, i'm married, so we can't go to my place. He lives in a share house, so we can't go there. We're both on the pension, so a hotel is out of the question. But.............we can come here for $50 and get $35 back from Medicare!!