Where is this "Take Me" sign?
HTTP, HTML, etc. are written as open standards so anyone can write their own implementation. Users might visit using Chrome, Firefox, Lynx, or a custom web browser that makes browsing real estate listings easier. You understand and accept that by using an open standard to deliver your content.
Nobody wants a web that is legally limited to just Internet Explorer, we want people to use open standards as open standards. Developers choose HTML and HTTP because it means anyone can use their content using their software of choice, otherwise developers would just develop native software where they have much more control of use restrictions.
When you put the content out there using defined open standards, you are saying "anyone who supports this protocol may access and use this content." It, again, is the reason why someone chooses an open standard over a proprietary solution. If you want to protect your content, put it somewhere that is not designed to be open for use by anyone.