Accepting robots + humans takes more resources than only accepting humans. Your arguments about revenue are website-dependant and it's the website owner who is

Accepting robots + humans takes more resources than only accepting humans. Your arguments about revenue are website-dependant and it's the website owner who is in the best position to decide whether robots are good for them or not (and plenty of sites don't ban bots in their robots.txt). In this case, the company that ran the bots is directly competing with Linkedin's products that sell aggregated data to employers and such, and linkedin clearly decided it's not going to lead to more revenue for them.