It's far more prevalent and rampant than you think.
Remember all those uncanny "coincidences" and other happening that you thought that were more than just random chance acts. As usual keep a list, do the maths and look for details, and you might find out that you are being snooped on.
The only solution for people that are found to have stalking tenancies is a global database with their details, like a sex offender register. Some people just can't be helped.