Mandatory Registration in Arcades?

I noticed that a lot of arcades (particularly ones running in GSS) force registrations after 5 or so plays. Why do you webmasters do this? I' never seen a benefit from doing this - I've always gotten more traffic increases/etc from letting members stay as guests. Is there a good reason?

 

As I see it your site gets more value with registered members and with this method you are letting them play as guests a while and if they want to continue to play on your site they have to register. I guess you loose some visitors but the value the registered members give is worth it in my opinion.

 

My question is - what value do they bring to your site?

What value do YOU bring to them when they register on a run-of-the-mill GSS? Nothing. That's why they usually won't register. Of course, they may increase the site's resell value or increase the value when you send out an email, but do the users care about that?

However, if you make registrations bring value to them, then they will gladly register in droves. This is how I got 12,000 registrations to one of my arcades and sustained 3-4,000 daily uniques (with over 1 million page views in a month).

I don't understand why arcade webmasters force registration - turning off many users whom may have enjoyed your site more (and still seen the ads) without registration.