You mentioned you're traveling in the West. We full-timed and traveled solely in the West the past 10 years with our 40' motorhome. Public parks are always our first choice and we never had a hard time finding a spot, including in the major national parks. We also love the forest service campgrounds and boondocking. You just have to do a little more research on campgrounds but there are many good reference materials out there. We've never been turned away from a campground because we couldn't fit.
We even use public parks in California but not their state parks. We have found gorgeous forest service sites and county parks in California.