No, it's not. It's nothing like that. Stopping goals is vital for the teams success, stopping the escaping ubervamps wasn't.
Case in point:
A- The were fighting in the daylight. This reduces where the vamps can run to.
B- The majority, if not all, of the town was deserted. This reduces casualties to nil if a vamp would escape the school, withstand the sun, and make it to someone's house.
The biggest thing was stopping as many as they could at the hellmouth, and let the mop-up crew mop up the rest, but the mop-up crew's job was hardly what I would call "important"