Most likely people who read along without being logged in.
People who read along and aren't logged, aren't counted. What matters to the host is the number of page calls and that is how one performs a DNS attack, by requesting more responses than the server can handle and that is what I experience, trying to read an email notification.
I am locked out, with a page loading, for the better part of 5 minutes. This is not a queuing issue, it is an international server on the world wide web and 100 idlers is not some sort of standard maximum, it is the virtual equivalent of zero - and even if it wasn't - the argument for the service provider is that it is going to take 5 minutes to serve up a page to all those 100 other users, before I get to see my email notification.
In the 1970's I went to a prep school that had a timeshare account with the Lawrence Livermore mainframe. I'd go to the computer room to play Star Trek and Lunar Lander. Since it was timeshare, you'd have to perform an operation, make a move and then wait for everyone else on the timeshare circuit to submit their task, then the computer would dole out the results, lander crashed, Klingon hit, calculation failed and the cycle would repeat. I could watch the cursor blink as each input was accepted and this situation at FSDeveloper, is like that. Dial up timeshare waiting 5 minutes for some small combination of ascii characters response.
Also, this is some sort of asymmetrical throttling, because once I make it to the page, everything loads normally. I really can't believe it is because the number of page loads drops from 100 to 99. However, $170/year is pretty cheap for the level of representation this site gets. It does host files and these guys don't just link images, the keep a copy, so storage is not such an issue.
What about the possibility of leasing server space from someone in the industry that would want to support developers, like LM, or someone?