Spyware, adware, hacker tools and other unwanted applications - that are often installed without the user's permission or knowledge - pose an escalating danger to data security, productivity, resulted wasted bandwidth, additional cost for protection, etc .
Some application such as keyloggers and other security-compromising programs, can provide unauthorized access to confidential proprietary information - for instance - financial and personal data.
In today world - any computer connected to the internet has some types of unwanted applications. Such applications are affected not only computers but some types of cell phones. Social networks that are very popular today - became a large source of "infection." Each year several millions new spyware and adware applications are created - the main reason for such activities - to earn money - that is becoming a substantial part of software industry.
From technical point of view - today any operational system may not function without antivirus sortware. Spyware more often affected government and even military networks, websites of large corporation - such information are in the news - and these facts are also negatively affect public's confidence.
While the law in most countries protect general public from spammers. If you search google with "hacker arrested" or "hacker jailed" - you will see number of examples of situations when an anti-spyware law works. But the practical effect is minimal - moreover - because of publicity - public's confidence about security of the Internet is decreasing.