Distances are distances. Unless they have the ability to instantaneously appear in different galaxies, they would need the ability to travel faster than light. Read up on the Kardashev Scale. Humans are a 0.72 on a scale of 0-5.Is a pigeon of high intellect because of its navigation skill? The scale of the galaxy is nearly incomprehensible to the average human, but it could be meaningless to an alien. Travelling to Earth may be like walking to the corner store to them.
Just sayin'