Welcome Mileena, you can always go to day parks that have picnic sites to cook a meal, I wouldn't suggest parking lots at all. We have lots of folks up here in Washington who, with their children are living in cars and we have nice little old ladies, who make sandwiches and take them around to where we know they live and feed them. Its against the law, but we don't care. A lot of them park at Park and Rides and Rest Stops and usually the cops just ask them to move on.
Also, my husband belongs to a fraternal order and they often have folks park in their parking lots at night. Its kind of a don't ask, don't tell relationship. All night grocery stores also might work if you can find a dark enough spot.
I would be out hunting for a small tent as there are usually a lot of city, county, state and national, campgrounds that you could camp at for little or no money. You can find some really cheap tents.
