Think of it like this. For the sake of argument, let's say the SiteSell servers are in Pointe-Claire, Canada.
When a visitor finds you in the Google SERPS, and clicks the link, it sends a request to the SiteSell computers that hold your site for everything that makes up the page. That request knocks at the doors of the servers, and the elves inside mark up one knock on their clip board, (ie one visitor) as having come to the door. They look at the request, get the various packages together (in the case of your Home page, that's 72 packages) and send them all off to the address they've been given.
They'll do this to any knock on the door, whether it's a bot or a human. They can't tell the difference, they're all just knocks on the door. The bots even sometimes give false addresses, say bot^(@)^trumptowers.com.
When the html file arrives at the visitor's computer, the browser puts the page together from the packages that are arriving. In the process of doing this, they come across the Google Analytics code. When the browser assembles the code, at some point it fires off a message to GA HQ, saying this page has just been loaded.
You can see these are 2 quite different scenarios. The SBI elves measure everything that comes to the door. GA is only fired when the page is assembled. If the visitor leaves very quickly, GA may not even fire. Maybe the bots at trumptowers don't even assemble the page, just read, absorb and mark their own clipboards.
If your SBI stats show an increase for a few days, and it's not on GA or Statcounter, then it's an increase in activity at the SBI server level, and likely an increase in bots.