Software Deletes Files to Defend Against Piracy

teamhasnoi writes: "Back in 2004, Slashdot discussed a program that deleted your home directory on entry of a pirated serial number. Now, a new developer is using the same method to protect his software, aptly named Display Eater. In the dev's own words, "There exist several illegal cd-keys that you can use to unlock the demo program. If Display Eater detects that you are using these, it will erase something. I don't know if this is going to become Display Eater policy. If this level of piracy continues, development will stop." Is deleting user data ever acceptable, even when defending one's software from piracy?"