I'm fairly new to working with WP but one of the things that caused me to switch from Drupal and C5 recently was WooCommerce. We could have a similar conversation about "WooCommerce Themes" as in, is there such a thing or is there just WP themes that support WooCommerce. It is really just symantics unless a plugin has some requirements where it literally won't work at all in some themes, which I would view as a major problem. Generally I feel the idea is themes create/enforce styling and layout for common features starting with WP. They then *try* to predict the additional features (from plugins) that will be included in the site.

This is the challenge with splitting functionality/theming in any CMS. As much as it's a positive and needed thing to do (separation), sometimes I'd wish for a plugin that really delivered it's own skin with it. Actually WP plugins tend to include more theming than Drupal module for example.

Back to my point about WooCommerce. Any theme could present WooCommerce pages, but only a theme that themes the checkout pages and controls the layout of important features like buy now buttons could really be called a WooCommerce theme.

How many themes out there are BuddyPress themes, and WooCommerce themes, and so on? If you add enough requirements, you'll wittle the options down to 0 pretty quickly.