Sandals : One pair of sandals should be brought for beach days and casual touring. They also will come in handy for when the showers aren't in the cleanest conditions.
Hiking Shoes : I brought a pair of hiking boots, which I still have mixed emotions about. The great part of the hiking boots was.... well it was the hiking. When it rained out it kept my feet dry and mud free, and when it was nice out they were still comfortable to tour around in. Issue with hiking boots is that they are bulky and heavy. If you can't tie them to the outside of your pack they can be burdensome.
Casual Shoe : A casual shoe should be brought that can be used for both walking around and going out in at night. Some places will not allow you to wear sneakers so it is important to have these available.