Agreed: it IS deplorable. No, not temporary. This is a neighbourhood defending its exclusivity, in a district that is all about exclusivity. No one there wants attended, visiting vehicles left overnight to tempt thieves and riffraff.
With respect to day-trips, it is possible to park more than 3 hours in nearby Whytecliff Park, but you have to get up pretty early in the morning to get a parking spot most days.
I have also parked on Pilothouse Road, which wends its way around the neighbourhood of Caulfield, just east of Lighthouse Park. I launched from the small dock just down the hill from St. Francis in the Wood, Anglican church. Hardier souls might try the beach access trails in Caulfield Park.