Couldn't an attacker simply run a script (from multiple source IPs) to get a large number of FB Messenger URLs - then parse the results for specific things - dr

Couldn't an attacker simply run a script (from multiple source IPs) to get a large number of FB Messenger URLs - then parse the results for specific things - dropbox links, google docs links and other services that are secured through a long URL? I would guess there are examples of services that would be high value to attackers and are secured through the URL... although I can't think of any in particular.