Water breaks stone pressure plate? (In plotworld only?)

If you go into a single player world or another world on the server (eg. /warp wild) and put a pressure plate next to the water,it doesn't break but strangely on plot world,it breaks

does it break when you place the water above or next to the pressure plate?

I have tested this and yes, the pressure plate breaks in plotword and not in other worlds. But I do not believe that this is a very important issue at the time being.