An elderly couple go to a physician complaining of non-specific sexual dysfunction, and ask the doctor if he will watch them having sex to determine if anything is wrong.
After their romantic session, the MD assures them that everything seems fine and sends them on their way.
One week later, they are back with the same complaint, and perform under his judgemental eye once more.
Again, everything seems perfectly normal and he tells them so.
Again, in one week’s time, they appear and have sex while he watches. The MD, confused, tells them “Look, this is the third time you’ve been in here, and NOTHING is wrong with the way you make love! What’s really going on here?”
“Well,” the elderly gentleman replies, “you see, we’re both married, but not to each other. So I can’t go to her place, and she can’t go to my place. Now Howard Johnson’s charges $45 for a room, but you charge $35 for an office visit, plus we can write off 30% of this to Medicare.”