I think the death of games in parks is also heavily related to the shift from day ticket guests to pass members. Today pass members are everything to regional parks. I don't have numbers to say this, but I feel very confident in the theory that people who visit your park even semi-frequently are dramatically less likely to play games—particularly on repeat visits.
Anyway, if you ask me, less games = a better park environment. My day isn't improved by people carrying around giant, anthropomorphic, Rastafarian bananas or dribbling basketballs all over the place. It's one of many small aesthetic/environmental factors that can make a park feel a lot trashier than needed.