These methods of obfuscation combined with websites, emails, documents, and PDF documents can be extremely tricky for users. Often, they are so quick to click, they don't realize they are being taken to the wrong site. If you combine this with registering domain names that are close to the target domain, they are very often overlooked by the end user.
Take an example of google.com being redirected to one of the following--g00gle.com, goog1e.com, and goog1e.com. Often these will easily be overlooked by the casual user, and you can have lookalike sites.