Included plugins are required to setup the directory listings, add listing products, create promotions, and other site functionality. Installing them is required in case you intend to use all the advertised features.
Once you activate the theme, a message in the admin panel will ask you to install the included plugins (see photo below).
Click on ‘Begin installing plugins’, and you’ll be redirected to a page where you can bulk install all the plugins at once. This message will also popup from time to time, asking you to update the plugins to the latest version.