Thank you for contacting us about your Membership plugin question.
Ecommerce addon and WooCommerce addon are different plugins. In the case you ant to sell content on the site you may use Ecommerce Membership addon.
In the case you want to sell products – you can install the Woocommerce plugin and then, to integrate it with membership, please use the WooCommerce addon by Supsystic.
You can see Ecommerce addon in use here – http://membership.supsystic.com/ecommerce/
and WooCommerce addon here – http://membership.supsystic.com/woocommerce/
on our demo site.