Waiting for the ball to drop...

http://www.theargus.co.uk/news/10157195.Holes_filled_in_with_concrete_as_golfers_play_in_Rottingdean/
http://www.dailymail.co.uk/news/article-2260837/Thats-rough-Council-fills-golf-course-holes-CONCRETE-prevent-people-playing-free-lease-ran-out.html

Pretty mean spirited. Might have been better to have put up a sign saying the course was simply closed until further notice.

I hardly think this would have been the first thing done to stop people playing there. It was clearly closed, but not sealed off sufficiently to stop people playing there, and while it was being used the council will have been liable if someone got hurt. I'm not saying that's a valid excuse for what happened but it's probably the reason.

I think Diggers lives there - probably getting his April Fools gig in early.

If I was just having a knock it could have been quite a few holes before I even noticed!

Assuming it is not being tended while closed, how long could players realistically have played on it before the grass was simply too long anyway?

Even in deepest winter (OK - it's never that bad here) our greens haven't got much more than a week (if that sometimes) in them before you couldn't play anything approaching golf on them.