Firstly, smart people know that we don't know everything, and probably can't, and science, as we have formulated it, can't explain everything. Its often the less smart and the wannabes that go around touting science as the ultimate yardstick for discovering and evaluating the "truth". History of science is ridden with examples, and that pertaining to all things of consequence, of how people kept accidentally discovering newer and newer forces in nature that always existed but are beyond human perception, so who knows what else awaits discovery. Smart people know and acknowledge this but don't say it out loud for it may be misconstrued as propounding esoteric theism etc, resulting in unfavorable branding, because science is in the hands of the mob, just like democracy is, and the mob lacks reason and knowledge.
Secondly, one must not conflate belief in a supernatural entity such as god, or even devil, and practicing religion rife with rituals and dogma. Its a major philosophical blunder that has been happening, again, perpetuated by the ones who don't quite understand these things and are eager to appear science-y.
Thirdly, when these amateurs attempt to disprove existence of god, they are really simply falsifying the assertions made by religions. Look closely. They take specific quotes from the religion they are attacking and show the absurdity of it using logic. This is far from disproving existence of god. They can't disprove because the believers cannot prove, and if you press them about it, the true believers that is, they simply say its their gut feeling, which is fair.
Another thing I find amusing is how the god denouncers challenge the believers to ask their god to perform miracles, like, say, curing a fatally ill person, by praying. This is again their imagination of what god is and what god does, which is basically taken from the religion they are attacking. These lot never cease to amuse me.
Now, does it mean god exists? I personally don't think so (actually I don't care), and I can't justify it beyond saying its just my gut feeling, which is exactly equal and opposite of the believers'. Debating gut feelings is futile. We can go into depths of human mind to answer this, but its a labyrinth we haven't cracked yet; we only have theories, conjectures and corelations.
There are three questions that humans ponder that I find to be incredibly waste of intellect - does god exist, where did universe come from, what is life. I find them wasteful since its my firm belief (ha!) that we will only find more bread crumbs but never reach the destination. I would rather people engage their intellect in improving the real and tangible, aka society.
Personally, I have no problem if a smart person believes in a higher power, but there is nothing redeeming about smart people who follow rituals laid down by religion, and I reevaluate my view about their smartness when I find out. In the edge cases where unquestionably smart people such as scientists, mathematicians, musicians etc are religious, I simply separate their achievements from their philosophical bent, and pity them for the latter, for there is no reason to discard beautiful art and hard science they produced just because they light a candle at midnight and stand on their head for three hours to please their god because their scriptures instruct them and their priest approves it.