Courtney Green, I think even if you could do this, it would be creating a ton of anonymous web activity in your instance for very little gain.
If someone sees your ad and doesn't convert, you won't have that activity in a viewable lead record. If someone sees the ad and does convert, you will know by default they have seen it if you are tracking sources with link tags. In either case putting Munchkin on the ad page doesn't really help you.
Munchkin cookies are domain specific so you wouldn't really be gaining insight on your existing known leads either (Re: Munchkin Tracking Multiple Sites )
What is the goal you're aiming at?