Couple of thoughts:
It’s obviously not the case that you need religion to be moral, or that religious people are on the whole more moral than non-religious people. Sophisticated and compelling moral reasoning is entirely possible without religion; just look at the philosophers of classical Greece, whose (non-religious) moral reasoning is still foundational for the western moral tradition (including, ironically, the Christian moral tradition).
I disagree with Trinopus that “atheists . . . generally create their own morality”. We all, believer and unbeliever alike, inherit a morality from our parents and our wider society. Part of growing up involves critically scrutinising that morality, and affirming, modifying or rejecting elements of it, but this process too is not carried on in a vacuum; it’s informed and shaped by our society and (since it goes on in adolescence) especially our peers. I really don’t see much evidence that believers and unbelievers arrive at very different conclusions. In fact, the degree of commonality between the dominant morality of believers in our society, and the dominant morality of unbelievers, is pretty striking, especially when you consider that there are both believers and unbelievers who assert that religious and non-religious moral thinking are fundamentally different processes.
I do think the impression mentioned in the OP is largely accounted for by confirmation bias. The real issue here is not the difference between religious and non-religious morality, but the distinction between living out moral convictions with integrity, and claiming moral superiority as a way of affirming oneself. (These aren’t fundamentally inconsistent - it’s possible to live a virtuous life and constantly call attention to it. The only virtue you compromise by doing that is humility.) If people are constantly banging on about morality, you’re more likely to notice that (and be judgmental of it) if they are people you disagree with.
Or, in other words, there are lots of people to whom religion is important, and who are not “selfish, judgmental, vindictive, apathetic”. They just don’t bring themselves to lissener’s attention. Conversely there are unbelievers who are complete shits, but either their shittiness doesn’t impact on lissener, or he doesn’t link it to their unbeliever status.
Finally, a footnote. It’s not a claim of any of the religious traditions dominant in the west that there believers are more moral than others, or that embracing religion makes you a more virtuous person. The dominant religious call their followers to live virtuously, but SFAIK none of them make any claim that religious faith is the only call to virtue, or the most compelling.