You're trying to reason about 'alien' intelligence in terms of human traits. What makes you think they are even interested in us at all? Maybe they just came here to re-up on potassium.
If aliens are coming here their motives could be anything including irrational or just non-rational.
I've speculated for a while that a "post-singularity" post-scarcity intelligence would get... bizarre... due to lack of hard scarcity constraints. It would just fan out across state space. It would be less Star Trek and more Lexx. Maybe they do make crop circles as interactive art. Maybe they do strange stuff to us to slowly convert us to their religion. Who knows? We can't know.