You may think the ants from the nearby anthill unimportant.
But there are a LOT of scientists that find them extremely interesting and studied them extensively. The same can be said about every bit of the natural world.
Plus, it's worth noting that life is the most information rich phenomenon known to man
; stars and black holes may have astronomical energies, but informationally, they're simplistic by comparison to a mere rat. Intelligent life and civilization is a further step above that.
And any species capable of interstellar travel must have a significant rational component (including curiosity/discovery, etc); 'drunken frat boys' - or their equivalent - just don't have the level of competency for such feats.
PS - We're already able to determine "every possible chemical combination".
That doesn't do us any good - the combinations are practically unlimited in number and only a vanishingly small number of them actually 'do something'; the rest is useless randomness.