According to the 8th Edition Core Rules, the attack stat is defined as follows:
Attacks (A): This tells you how many times a model can strike blows in hand-to-hand combat.
As I understand, this only affects the fight phase, and as such only melee weapons. However, I see several units, such as the Kustom Boosta-Blastas, which have an attack stat, but no melee weapons. What is the purpose of this stat? Or is it just "filler"?