Create a new collection for user profiles?

I am new to meteor. I have read a lot about the profile object in the users collection. I understand that the user collection acts differently than other collections in that it is writable from the client. So my question is, why not just create a new userProfile collection instead of using the profile object in the users collection? Would there be problems joining the profile collection data to the user collection data? What’s the best way to have secure unwritable profile data? allow / deny rules?

Any ideas or thoughts?

I think the Meteor Guide may be of use here.

Thank you! I didn’t know that guide existed. That’s exactly what I was looking for.