In the past week, the largest United States banks have pledged to temporarily zero out their customers’ negative balances so they can get access to their stimulus money and put it toward whatever expense seems the most pressing. Negative balances typically include the various fees that banks tack on to customers’ accounts for letting the customers withdraw more money than they have. However, some regional and community banks — which often serve areas where there is little competition, including poor neighborhoods and rural communities — are pursuing different approaches.