Do fire man still ride on the back of th truck sometimes>?

ok so i figured that now fire trucks have up to six seats in them. so there would be no need to satnd on the back. however many fire trucks i have seen throughout various cities have places to stand on the back and even bars to hold on to. but i have never seen a firreman actually standing on the back. so do they still ride on the back and what is the purpose of the bar and ledge to stand on?