Public sector bodies are always more complex than their private sector counterparts. A bank has to move money around. A local authority has to move money around, maintain houses, make sure children are cared for, make sure vulnurable adults are cared for, lend books out and keep said book repositories open and warm for those unable to get warm anywhere else, make sure the non-vulnerable children are able to read and do sums and allow a bunch of elected political types tell everyone to do this stuff.
I work in a University now and that has its own set of complexities. Heaven forbid that I find my way to central government!