It isn't illegal for software companies to protect their products from people who like to make "backups" any more than it is "illegal" to have an alarm on your car to prevent theft.
Years back, when programs were published on (unreliable) 3.5 floppies, the publishers encouraged "backups". The current CD ROM/DVD media is extremely reliable and there is no valid reason for individuals to make a "backup" - unless they are planning to distribute the program to their friends - or go into business selling "backup" CDs on the Internet.
Software companies that have a licensing agreement which prohibits the making of "backups" also have a replacement policy for defective media. It is extremely rare when someone has to buy a NEW copy of a program to replace a defective CD. Of course, if you loaned your original CD program to a friend and didn't get it back, then you've got a problem