Note: the beam wasn't a tractor beam it served the purpose of draining the shields. Later they muffed this up in Emissary because the Beam is clearly blue that does the same task.
Well it also had them trapped so if it isn't a tractor beam, what is it? It's uh... it's green.
The point is they didn't spontaneously decide to make everything green in FC, they were just beefing up the original style.