Tracking & Rat game
Simply because all of the third-party commenting systems have bunch of trackers on them. The moment they start rendering their easy to run widgets, you'll be shocked and confused about the amount of trackers, advertisement systems and bunch of other non-sense services start to track you. This doesn't make sense, why a commenting widget would require that much of monitoring ? That's horrifying and not-acceptable.
Building a commenting system from scratch is not easy, it has a lot of complexities, security practices, notification system both based on email and in app notifications (real-time, we have that planned ;)), moderation, flagging and many many more. All of it could be solved by using a easy to run commenting system from third-party. It's literally less than 10 lines of code and it's done.
That comfort comes with a price, the price that our users should pay with their privacy and we don't want that, in matter of fact we hate it.
We want GoNevis users to feel safe, being respected especially about their privacy.
This is the reason we're building many in-house projects to keep our users happy.
Everyone deserve privacy and we do whatever we can to support it.
ps; We're using Google Analytics, we should get rid of that too, any suggestions ?
http://getclicky.org is a good analytic tool