That is (or was) a fairly typical sight in much of Washington, DC until just a year or so ago. They found that several thousand covers were missing city-wide. This only occurred after several shocks or electrocutions had occurred. The public works department claimed that the reason was that these poles were very old and that parts were obsolete. They eventually ended up fabricating stamped steel "generic" covers that were secured by stainless steel bands in an effort to provide some level of safety. I suppose that something is better than nothing.