You have a bunch of laptops running software that accesses services that are normally restricted (like access per IP or IPs from certain countries would set off alarm bells) the client paying for the laptop can run something that does the work or submits the work from the IP address space that is OK. I contracted for one company and saw an office that had one department with a closet full of laptops scanning Craigslist ads because they were getting blocked if they didn’t take this measure but don’t know the details but they figured out a workaround and automated it to scrape data daily from all Craigslists regions daily.
At many jobs it will need to be more sophisticated than simple IP spoofing, because the laptops have EDR software installed to monitor employee usage. It would be suspicious if the employee laptop is doing nothing but proxy internet traffic.
I suspect these farms have full-fledged remote KVM setups.
