There are TONS of non-runners who have PF - it's actually really common in the sedentary population that spends time on their feet.I actually find my PF flares more when I'm NOT running than when I am.
PF can also be really localized - mine is on the medial inner side of the back heel. Get a night splint, and spend some time stretching with that big toe in full extension as well. Calf raises with your toes on a towel.
Could also be fat pad impingement, but the connection to the big toe makes it sound like PF