The primary benefit of using 'fw monitor' over 'tcpdump' is that 'fw monitor' allows you to see the inspection points, which cannot be seen in 'tcpdump'. 'fw monitor' is specifically designed for Check Point firewalls and provides detailed visibility into the packet's path through the firewall, showing how it interacts with various inspection points. On the other hand, 'tcpdump' is a more general-purpose packet capture tool and does not offer this advanced functionality tied to Check Point's inspection processes.