Day hiking boots are not drastically different than normal hiking boots but they are just as important. A lot of people think that since they will only be hiking for one day, maybe even only a few miles, that they can just wear their tennis shoes. They often end up with blistered feet and twisted ankles.
It is always worth it to wear hiking boots when you are walking in the wilderness. A good pair will last you years and you will be doing a huge favor to your feet.