Why is Wed predicted to be so crowded?

I was just curious why Wednesday is listed as the second most crowded day at the parks. My guess would have been Mon or Fri based on people coming from out of town and staying over the weeekends. Any rhyme or reason for the midweek spike?

Thanks in advance!

As far as I know, it's because people often try to go during the week, to avoid the Saturday crowds. However, everyone seems to pick Wednesday, making it (compared to the rest of the week) busy.

Fair enough :) Thanks!