Yes, thank you for this good suggestion! I agree that there should be an option to prevent the use of vacation time in tournaments. I am sure this option will become available very soon for those who want to run tournaments without the use of vacation time.
Vacation Abuse SOLUTION

but wait. what about the occasional good people that actually use vacations truthfully?
i wouldnt want to be on that end.
Well, maybe you could set it up so people can only go on vacation once or twice or a set amount of times, regardless of how long it is. That way if someone actually needs it they can use it, and hoepfully they only need it once.

People who sign up for a tourney will know in advance that auto-vacation means a loss. They can't complain if they know in advance, IMO.

How much more difficult would it be to replace the simple all/nothing approach with a "Max Vacation Days Per Game" control in the tournament configuration?
If you're a TD who's developed a zero-tolerance policy for vacation, then there's nothing stopping you from entering zero. On the other hand, you could allow a modest 2-3 days vacation per game, which would prevent significant delays and still allow for the occasional personal emergency or unforeseeable circumstance, etc.
(I can appreciate this would probably add a lot of complexity to the development effort.)

With all of the many many tournaments available, I really don't think we should waste one more second on worrying about hurting peoples feelings that insist on using vacation time. I'm all for seeing non-vacation tournaments available for people who want to finish a tourney in under a year . Wonderful idea LEE2000. I think it will make a difference in subscribers too. When I think about paying to play in certain member only tourneys, only to have them bogged down by vacationers, it makes me think twice. But, if I had the option of vacation-free tournaments, now that's a good selling point. I think there are a lot of people that would like to play in tournaments, but don't because they don't want the hassel.
It's this simple:
When setting up the tournament have a "YES" Vacation or a "NO" Vacation option. "No" Vacation means just that, "no vacation", when your time runs out you lose just like every other "over the board" live tournament played everyday all over the world. An on-line tournament should be no different. That is an option that should be made for Premium Members who want to run tournaments. The programming should be simple enough and that would solve most of the problems.