What a stupid thing to say "What do they want from us, nothing"<br>What about our Planet, which enables life. Living is quite awesome. Maybe they would want to keep on living.<br>Personally I think the Universe is a dark forest. In short this means that every civilization will destroy another civilization as soon as they are found.  See "Dark Forest Theory",(reply>), If they want a planet which enables life, assuming they are immortal and keep reproducing (=they increase in number quickly) they could colonize many exoplanets which have no life or have primordial life, unless they wanted (and could) colonize every single exoplanet