@Oxy You and I seem to have posted at the same time, so I do not know if you were able to read my reply before posting.
Yes, the kind of site that I am testing would consume a lot of server resources if many people were using it, which is why you can rest assured that I will not publicize the site unless I upgrade to a suitable hosting plan.
So shouldn’t hosting such a site on a free account be fine as long as the site only has a couple of people visiting it? If the site is continuously swarmed by a multitude of users, feel free to suspend it, but it feels unnecessary otherwise.
In fact a link you posted says the following:
What to use instead AJAX - #3 by Admin
The question “how much AJAX is too much AJAX” is impossible to answer for all sites. It really depends on how your website was built, how many people use it, and how often you query the server.