Naturally dive boots provide protection for your feet both topside as well as during the dive. They protect your feet from not so friendly shore entries as well as provide a layer of protection from possible stings and bites due to marine life you may unexpectedly encounter on your dive.
Alec Pierce answers questions and discusses how to select dive boots in the clip below.
With all of that being said, dive boots provide a level of comfort for your feet. They protect your feet from chafing due to direct skin to rubber contact with your fins as well as provide warmth for your feet when on colder dives.