I have seen parties there set up just in that manner, I'm not sure if you supposed to get a permit or anything but it's usually not crowded so you shouldnt have a problem .
I don't know what the official rules are...a quick check of the GVRD site only says that there are no bounce houses, smoking nor alcohol allowed in any parks. https://www.gvrd.org/gvrd-parks/
Yes..it is pretty much do as you wish..
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