Sure, but where do you stop with this line of thinking? What if the aliens are giant gas clouds that have trouble with the whole idea of planets? What if the aliens are fluctuations in plasma flows inside a star and don't realise there's anything outside their environment?
As far as we know, there's nothing out there. As far as we know, we're the most advanced life form in the entire universe (for a given definition of "advanced"). As far as we know, every exoplanet is teeming with civilisations. We know nothing. So if we are engaged in speculating about aliens, then speculating that they're probably like us, while allowing that they may not be, seems to me to be the only sensible thing to do.
As far as we know, there's nothing out there. As far as we know, we're the most advanced life form in the entire universe (for a given definition of "advanced"). As far as we know, every exoplanet is teeming with civilisations. We know nothing. So if we are engaged in speculating about aliens, then speculating that they're probably like us, while allowing that they may not be, seems to me to be the only sensible thing to do.