The site is about a particular type of pipeline cleaning (think water/oil pipelines). I am certain that nobody was asking about this particular site or even the industry its in 15,000 times a minute 24 hours a day.

It's much more likely that their crawler is just garbage and got stuck into some kind of loop requesting my domain.

I suppose that they just keep referring to the website in their chats, and probably they have selected the search function, so before every reply, the crawler hits the website