The first thing to remember is that, even though you don’t need a licence or registration to fly a Mini because of its weight, all the other regulations that apply to drones still affect you (and me too by the way).
Rule of thumb: Know the regulations as they apply to you and ask permission if you’re flying anywhere where other people are nearby. I haven’t tried it yet but I’m guessing that, if you plan your flights for a time when very few or no other people will be around, you may have an easier time getting permission to fly in many areas that would normally be restricted.
Not directly related to flying in parks, but the way I try to deal with people who are nearby and curious...
I haven't been flying long but
EVERY time I set up within sight of people (beyond the 30m distance), someone will come over and ask about the drone.
I'll chat and answer their questions and when they ask if I mind if they watch, the conversation pretty much always includes something like:
Me: "I'm not legally allowed to fly within 100 feet of anyone who isn't part of my crew."
Them: Look of disappointment.
Me: (If I think they'll follow my instructions and actually help observe VLOS) "But, if you want, I can make you part of my crew for this flight."
Them: Look of enthusiasm
Me: "That means a couple of things. First, if I tell you to move - it's probably because there's a problem. If that happens, move away quickly, but be careful not to trip over anything. If it sounds like I'm giving you an order, it will probably be to prevent an accident - the propellers spin pretty fast and I don't want to get blood all over them. Is that ok?"
Them: Puzzled look, then realization - maybe a laugh. "Yes"
Me: "Second, I have to be able to keep the drone in line of sight the entire time it's flying. I'm going to be concentrating on it but I have to land it very quickly if there's any real aircraft in the area. So, your job will be to look around every few seconds to see if there are any planes or helicopters coming nearby. Can you do that?"
Them: "Yes"
Me: "Welcome to my flight crew! I have to finish my checklist before I take off. Want me to tell you what I'm doing as I get ready to fly?"
Them "Yes" - usually with a big smile by this point.
Me: "Ok, so I have to ..."
And off I go.
About parks, though, the 'rules' can be kind of funny. For example, there are places that you can't take off or land in the park, but you CAN fly in/over them.
Get in touch with whoever controls the park - local bylaw (call 311 in many places in Canada) and ask.