So they will buy an unprotected competitor's product instead. If the software producer were clever they would give two dingles with every product, so that if one went bad the consumer wouldn't be inconvenienced. It would still be illegal to give away a copy, of course. Computers copy things all the time. The execution of software requires making a temporary copy of it in main memory.
Backup software makes copies on other media.
Networks are becoming common, even in individual homes. Networking means that software is often shared between many machines. The executable copy may reside one place but copies are made on whatever machine needs to use the software. All of this really violates copyright unless there is a long contract which defines what can and can't be done by the individual. But then it is not copyright law that is really operating, instead it is contract law that is working.