Why is it socially acceptable to believe a god may exist, but not that extraterrestrials may exist?

i've never seen god, i've never seen jesus, i've never seen muhamad and i've never seen an alien. i don't need to see to believe. look at it this way, with all the available star systems and building blocks of life just waiting to be used, it makes sense that we are not exclusive in gods creation that we are not the first, nor the last. i'm not bothered by it, nor should anyone else be.