The blogosphere, at present, has 'sponsored themes' as the buzzword. For those who are new to the topic, the term, also called 'theme sponsorship,' is used in the market involving advertisers that pay money to sites in order to have plain-text links back to their properties. As such, they could rank better in search engine results.

Some theme authors use deception to hide the links or other ads in the template so most people will either never notice or not know how to remove the ads. The unethical SEO techniques they employ are obviously hated in the industry. But what one saddening fact is that they exist to play around in the SEO competition.

These iniquitous authors do the trickeries without telling their users it's a sponsored theme before download, or use CSS or PHP tricks so most people will either never notice or not know how to remove the ads.

On the bright side of it, there is another type of themes that disclose up front that the themes are sponsored. And there are 3 main issues to consider: First, Google penalizes websites that promotes things that the search engine considers spam. Second, many users of WordPress may not be aware about the fact that they will not be able to properly modify their templates to remove the bundled ad. Third, many of the themes are trying to legally preclude you from removing the ad link.