My father and I split the cost every year. I'm 32 years old, and haven't been "a part" of my father's household for over 12 years.
I have no problem splitting the cost with him. We have one computer. He has one computer. He has a mac because I convinced him to buy one.....after I convinced him to buy a couple thousand shares of AAPL at $13 a share back in 2000/2001. Buy the family pack and share the license. You're doing the company good.