Theme Sites. These are of course thematic, which will be helpful on what theme you want to use in a page. Scrapbooking is like Wordpress. If you are making a website powered by Wordpress, you will look for nice themes that you can work on instead creating your own. It should be appropriate in the long run as you post and update it. In scrapbooking, templates will stick for a long time after some time of adding all the elements, and it will be the basis of the overall look that you can't change. Photo Sharing Sites. These sites are both theme and group sites at the same time. Photo sharing is mostly their goal, but I have seen scrappers post their layouts or projects. So you will get templates or their ideas as well.
Buy business web template with total customization option. You may get layouts in the market designed superbly but with little scope of customization. On the other hand if you go for open source developments like the Drupal, Joomla or others then you should buy layouts designed for particular themes. Otherwise your developers or the designers will face problem to make layouts completely fit for your business. Even in SEO related changes there will be problem.