OK but this does not make it right, just because you have not been prosecuted only means it's not been instigated yet. There are no big deals or monies to be earnt here. But it's still illegal (in fact). If you include the copyright symbol you have a defence if it all goes wrong.
Under UK law (the position in other countries may differ) copyright material sent over the Internet or stored on web servers will generally be protected in the same way as material in other media. So anyone wishing to put copyright material on the Internet, or further distribute or download such material that others have placed on the Internet, should ensure that they have the permission of the owners of rights in the material.
Generally, when you put your work on a web site, it is probably a good idea to mark each page of the web site with the international © mark followed by the name of the copyright owner and year of publication. In addition, you could include information on your web site about the extent to which you are content for others to use your copyright material without permission. Although material on a web site is protected by copyright in the same way as material in other media, you should bear in mind that web sites are accessible from all over the world and, if material on your web site is used without your permission, you would generally need to take action for copyright infringement where this use occurs.