After deploying my 1st exchange 2013 and setting up a new public folder I noticed that i have to assign certain users to the public folders. Can I not assign "everyone" or a group to the public folder instead?

Brad,

If I understand correctly, you are talking about permissions. You can assign permissions to entire groups instead of individuals, and in fact this is the recommended way of doing so.

If you want to have some folders to be actionable by all users in your organization, you can assign the permission to the special user "Default".

Let us know if that solves your question.