I was just alerted by a contributor to something from the local paper last week, from Wednesday's Wisconsin State Journal (click to enlarge, of course):
The question is the verb 'to finch'. You have to wonder if this isn't a blend of 'to pinch' in the sense of minor thefts and 'to filch'. Indeed, the Dictionary of American Regional English proposes that for the one attestation of it that they have — from California. Of course, it's possible that westward movement got a local Wisconsin term to the west coast.