I wanted to ask this because i have no clue how there are, as of posting this 22 members active and 3,100 guests, is that number accurate or are they mostly bots?
So many bots. If you click on the "Members Online" header (or just here) it'll actually take you to a page where you can see what they're looking at, which I find quite interesting. There are a lot of old trading threads and unknown (non-existent or archived) pages in there for example, there's no way those are useful to anyone.
I can only assume they're looking for threads to place spam posts in, or more likely, we're being scraped for data just like the rest of the internet. But at least the computer can now generate fitting misinformation to any question you may have, and that made the shareholders very happy so it's all worth it! But not really...
Sometimes I feel that the massive amount of guests are guests itself, bots and some users on here that lurk while signed out.
I also lurk on the forum sometimes before logging in.
It's bots unfortunately. The bane of the Internets existence, and why a lot of people believe in the dead internet theory. I liked it better when it was just forums, but now it's a bunch of social media controlled by corporations that are pretty much mind-controlling the public.
I have a forum I created that had maybe a handful of members from a forum where the admin disappeared randomly. I made the backup in case something happened to the forum since none of us had admin controls to fix it if it became a problem. It's pretty much long dead, years ago, but for some reason the most users ever online is sometime in 2021 long after the forum became dead. Like 240 on at one time. I'm not even sure what caused that bot spike.
Those are the bots that are kind and transparent enough to openly disclose themselves. Historically, these were primarily for search engine crawling, and what finds the content on websites for a search engine like Google to show you. Although some are also for ad context purposes too as you suggested.
These days, many of these will now be for scraping training data for AI systems. (this article from last month might be worth reading for some potential context) Or others may be for posting spam, as Mick said. The Robots list are only the ones transparently disclosing themselves -- there are likely hundreds or thousands more in the Guests list which attempt to disguise themselves as regular users as they do not want to be restricted from any activity.