Just a thought...
I have a fair that lasts for 4 days.
The weekdays open at 18:00, whilst the weekends open at 16:00
How about implementing daily opening hours if they are different, rather than always assuming all days have exactly the same times?
I also know of several fairs whereby they take different entrance fees on different days... actually I also know of some events that charge differently according to what time you get there...
It is probably tricky to control this stuff... I assume that since I have always wanted it, but never seen it on any event system (and I think I have tried them all).