Hover boots were a special type of boots that allowed one to hover. These type of boots were used in some forms the sport known as grav-ball, but not under Corellian rules, or the rules used on the planet Lothal either. As such, some players who were raised on the type of grav-ball played without hover boots, such as Merei Spanjaf, came to be dismissive of the version played with them as not being "real grav-ball."
In grav-ball as seen in Star Wars Legends sources, the game was always played while wearing hover boots. Jason Fry, however, didn't feel that this "spacey" aspect worked for the Servants of the Empire: Edge of the Galaxy story and thus invented a new variation that did not require these boots.