Tigermoth we have a trampolene and my kids are on it every day... not usually after 8pm, though. Neighbour has a 5yo in DS1's class, I am sensitive to not being a bad example to him (even though neighbour's boy needs more sleep than my children).
Yes, they do seem a lot of fun (we've had ours 5 months & the kids still love it).
However my neighbour (as it happens) had a trampolene for 5 months before us, and although I would loved some invites for my kids to use it, they weren't forthcoming, nor did I think they particularly should have been -- I have been more concerned that ds1 isn't invited around hardly ever, rather than about whether he went around to theirs to use the trampolene per se.
Excuse mad typing, am slightly tipsy so may not be making sense.
I was thinking about this thread last night in bed when I couldn't sleep (as you do). I said before that my house was "the" open house for neighbourhood children for awhile, which was fine, but I never hesitated to throw them out if they were rude or awkward. I think shrub should tell her neighbours that some of the children visiting her trampolene have been rude (it's true) to her family & children. She can't nicely say no to some without saying no to all, so just say no to all except for special occasions (ie., organised playdates).
I still find this whole situation baffling, in a country where everyone knows that "being overlooked" lowers the value of your house, and people fret about parking on the public highway outside somebody else's house, suddenly it's ok to have the all of the street (and more) children use your garden as a public playground. I think maybe I've stepped into a twilight zone...
Off to babble on another thread, me thinks.