Consider this: nothing can prevent a thief from breaking into your house if they really want to. Those locks and security systems which homeowners install throughout their property can't stop someone from breaking a window to gain entry for example, or picking the locks, or in extreme cases, simply driving a stolen car through the front of the house. In fact it doesn't even require a 'hardcore' thief to overcome a property's protection. Through the simple technique of Lock Bumping, virtually any lock can be picked within 5 minutes and without a trace. In the spirit of DRM hysteria, here's a more sensationalist take on the issue: Nearly Every Lock You Have Is Now Worthless. Even if you upgrade your locks to try to overcome this vulnerability, consider the new SneaKey technique which allows potential thieves to create perfect duplicates of keys using only some software and a standard resolution digital photograph of the key - even from a picture taken at a distance of up to 200 feet away.
So really, all locks and keys do 99% of the time is present a constant inconvenience for legitimate users. If we lose them, we're locked out of our own houses or cars. Yet strangely enough, you won't find a groundswell of popular opinion stating firmly around the Internet that "door locks don't work!" and demanding that everyone remove them because of the inherent inconvenience that they impose. Why is that? Probably because everyone is the owner of physical property of some kind, and is willing to endure the constant inconvenience of various locks and keys in their daily lives in the hopes of protecting that property from potential theft, even if in reality it actually provides them with no real protection against most thieves. However because most people are not owners of intellectual property, they find it exceedingly easy to flippantly shout simplistic solutions across the Internet such as "Greedy companies must remove all protection and DRM, they don't work!".