I'm posting this not in the form of defense, but, more in the celebration of reality. You do not take down a crane that size everyday. Why, because it is an 8 plus hours of labor to do so. If taken apart everyday it would involve 8 hours of assembly and another 8 hours of dis-assembly leaving only 8 hours of usable time. With what they are doing, it would still be up during the day.
Part two, because I know someone is going to suggest it. No, you cannot just lower the boom so it isn't visible. The castle is 187 feet high and the crane towers over it that would mean that you would need to have a space that is about 230 feet long to store the entire crane out of sight. Can anyone think of a place where that would fit on a daily basis.
But wait, I've seen the lower part of the crane, it's on wheels and is on a truck type bed. They could just drive it out during the day if they cared. OK, let's go back to the length of the boom. To do that they would still have to dis-assemble it to move it out of the park and not knock down any buildings in the process.
In January, when you said that you only saw them work about 15 minutes in 9 days, you are probably quite correct, however, during that time they were taking down the Christmas lights. They were only doing that at night. Now they are doing other maintenance and a lot of it, unless you look up behind the turrets or on roof tops is not visible by the public.
Once again, the realities of procedure and common sense conflict with our vision of what fantasy should look like. That fact of the matter is that you cannot have fantasy without reality setting it up.