Why is this service free?
This is a part time effort. Currently I'm called on to travel often, making it difficult to ensure that the site updates every night.  So occasionally we may miss an update.  As it's set up, the automated programs that I run every evening create the systems here even when I'm on the road, so it's ony if problems arise that an update will be missed. 

Publishing this site helps me with the discipline to follow my systems full time, and I enjoy the fact that some folks see value in following the system.

If there's enough interest it would eventually become a paid service, but the level of service I would insist on providing (e.g redundant servers, email notifications of trades, expanded system offerings) to make it worthwhile for both me and my customers requires more time than I have available right now.

I've recently started tracking the number of users of the system, and if the interest level warrants I will work on upgrading the offering to an improved paid service.

So, for now enjoy it for free.