How would you like it if Inspector Clouseau barged into your office, looked over your shoulder as you ran Excel from a network server, and asked, "Do you have a liesaunce?"
"A liesaunce?" you reply, puzzled.
"Yes of course, a liesaunce, that is what I said. The law specifically prohibits the playing of a computer program on a network without a proper liesaunce."
You don't want to get in trouble with Inspector Clouseau, do you? License that application.