yes definately for ninjutsu.
although we call then body skills, and its more like rolls and cartwhells, wheel flips but im not so sure about flips, but yes ninjas always need to look good when assasinating people
on a serious note, if I were a ninja and part of a tribe I would want to learn unreasonable amounts of acrobatics because the samurai thought ninjas were deamons, so why not play on that and fight unnaturally.
just my take on why a ninja might need acrobatics