If you have no players, check in with Game Central. Often they have players that do not know what they want to play. This would be in addittion to picking up your sign in sheet about 15min before the event. If after 5 to 10 minutes you have not been able to get any players make sure you let Game Central Know.
It is not unheard off to have no players, we expect some events will go this route. What we dont like seeing is Players showing up and there not being a GM. If you have let Game central know they may get you players, or we have had some cases where players and GM's were both looking for each other, but were on the wrong tables. Game Central sorted that out.
Once Game Central says your games a bust, go have fun and play.
On the off chance everyone of your events some how busts with no players, we track that and sometimes we need to look at other event options. It could be that there is no players that want to play Game X, but next year we could redirect you to games that we need GMs to run.
So the short answer, no just check with Game Central before you toss in the Towel.