Warping a ship up against a pier, dock, quayside, what have you is also why you will see a lot of the yards struck down, and jib booms hauled back over the bowsprit.
Now, this allowed for work to be performed on those vital pieces of equipment, as wrll as allowing for more ships in crowded spaces.
For some harbors and some ships, they did not dock at all. Instead, they anchored in the anchorage, and lighters came along side to tranship the cargo. Lighters had very simple sailing rigs, mostly to allow for more stowage. Some were specialized, too, hauling water, or livestock. or chandlery items. Very real advantage in using lighters is that you can unload from both sides of the ship. Or you can load from one side and resupply from the other.