I just want to say that some of us take trips, planned at the last minute. Nothing like a buddy calling and inviting you to an impromptu elk hunt, or maybe your wife's had a bad week and needs a quick road trip out to Seattle for some shopping and shows. If I can get out of work for those endeavors, it seems funny that the one place I'd be penalized in a website I pay to use for my relaxation and mental health.
Just my two cents
instead of taking out vacation, this feature should be synchronized with both online and live chess so one on active vacation should not be able to play until the vacation time is taken off.