Anyone running a website should take into account the legal ramifications of earning money off of your visitors. Many countries require a website to provide anyone reading it with a full rundown of all the information they might be gathering. In fact, if you're running Google Adsense on your site and don't have a privacy policy available, you're technically within breach of contract. Creating a proper privacy policy can be a major hassle for many webmasters. There's a lot of "legalese" involved and failure to properly parse the language can lead to potential lawsuits.