1. Fortunately, we are able to remove the posts that are undesirable before most people see them. Obviously, this is one factor that has increased our administration load, and part of the reason for the topic to be brought forward for discussion.
The benefit to us (actually a benefit to the users just as much as it is to us) is we have a much lower rate of completely useless posts from people looking to, well, troll. Also, users who register stay here longer and help build the community.
2. The benefits stretch quite a bit further than private messaging and the ability to upload photos. E-mail notifications; new message statuses on the home page and on all post and post listing pages; time offset change to adjust the times to your local time zone; user profile; color theme options; forum home default preference (categories or forums); default sort order preference; default display mode preference; default thread view preference; total threads and posts to show per page preferences; header placement preference; preview post screen preference; text box size configuration, and more. This list will only get longer with our upcoming upgrade, and trust me when I say we get dozens (if not hundreds) of requests for features, and if we starting taking features away, I'm sure we'd hear first from those who
don't care if the features are there or not about how they want them back... so the reason the features are there is because the users want them, and use them.
3. Members encourage other members to do certain things ... none of this is required just because you register. All that is required is you enter one e-mail address, secure your username, and login. it takes 10 seconds and if you so choose, you reveal to the forum nothing more than you did as an unregistered user.
The bottom line is registration keeps the forum more organized, more responsible, and ultimately benefits the community as a whole over any one person or type of user.
This
isn't to say we're going to require registration.