Ignorance is not a pejorative term. It is synonymous with uneducated, and of course there's no shame in not knowing something, especially something that's obscure. I am totally ignorant about how to write programs in LISP. This doesn't mean I'm stupid (unable or unwilling to learn) nor that I'll always be ignorant of this subject (although I think I probably will.)
The "view a friend's history" thing is some social engineering/sleight of hand. They don't offer to let you peek into other people's browsers. They offer to let you send YOUR OWN browser history to a friend. When you do this, you are giving your browser permission to send the information it has collected to startpanic.com, which seems to me further evidence that they are not collecting this info behind the scenes.
BUT - once you send your browser history off somewhere - THROUGH THEM - they then have access to the information you provided them. They can then store it and show it to your friends, should they request it. If they can trick your friends into sending them this info as well, then they can store it and show it to you.
But there's still nothing technically sneaky going on here. Your browser collected some information, then offered to let you send that information on to a third party. If you do this, the third party (startpanic.com) is collecting information with your permission, since you had to actively do something to send it to them.
Once they have your browser history, you might claim that they shouldn't store it and show it to other people, but they did kind of tell you that's what they were going to do, although not in so many words.