Did you know you can comment on a page without “liking” it? Allowing people to interact with your page without “commitment” could encourage more activity. It also implies that people who do like your page are true fans.
You can also “subscribe” to profiles. For example, if you want to follow to updates of someone well known in your field, but not become their “friend”, you can subscribe to their profile. Of course, people will have to allow subscribers and will also be able to see who has subscribed to them.