Why is the West Bank not called the East Bank?

Bank of Hartington 4 Bank of Salem 13 Citizens State Bank & Trust 4 COLUMN National Association 5 Community Bank of Memphis 1 Community Banking Company 6 Cowboy State Bank 1 CREWS B&TC 7 Empire State Bank 3 Farmers Savings Bank & Trust 2 First Bank of Okarche 3 HNB National Association National Bank 14 LAKE RIDGE Bank 15 Security State Bank of Hibbing 6 TEXAS FIRST Bank 9 THOMASVILLE National Association National Bank 5 TRUPOINT Bank 13 UNIVEST B&TC 5 VIRGINIA National Association National Bank 7 Welch State Bank 9