To answer that, you need to understand how Simplero works "under the hood".
We have several objects in Simplero. One of the central objects, of course, is the Contact object. A contact has name and email, plus whatever custom contact fields you've added.
Though, when you're sending a Broadcast to a List, we're not just sending that broadcast to the Contact subscribed to that list. We send it to the Subscription on the List. The Subscription, in turn, is a "wrapper" around the Contact, with extra information.
When you send to a Product, we don't send it to the Contact, we send it to the Participant or the Purchase. The Purchase or Participant will be a "wrapper" around the Contact, which will have extra information.
Here's the breakdown:
If Purchase contact and Participant content are the same, the Content URL for both will be the same and include both billing stuff and content. Otherwise, they'll be separate.
Segments are tricky because each member of a segment is actually the wrapper object. So if you create a segment consisting of all the purchasers who completed a purchase of a product, each Segment Member is actually going to be a Purchase object.
So for a Segment Member, the Content URL will be the same as for the wrapper type that is the Segment Member. I hope that makes sense. This stuff gets complicated fast.
Automations as well are not populated by just contacts. They're populated by their wrapper objects such as a Purchase or Participant or Subscription, etc.
Easy. Just go to the page in the Membership, copy the URL from your browser's address bar, and insert it into the email as the same way you would a link to a story on Buzzfeed. No magic required.
I hope this helps clarify things.