In the real-world this restrictive sense of the term "atheism" has been eclipsed by the inclusion of a myopic belief in the view of scientific materialism. This is the atheism being touted by popular authors such as Richard Dawkins, Sam Harris, and even Stephen Batchelor and other Secular Buddhism folks. Materialism is incompatible with Buddhist rebirth, and related teachings.
But this misses the point that what you are calling atheism is not inconsistent with the practice of the Buddha dharma, or with its morality. Materialism is incompatible with Buddhist rebirth, yes, but it is not incompatible with the morality that is the point of Buddhist rebirth.
The folks who were surveyed who put atheists in their least-trusted (right down there on the same level as rapists) list of people do so out of fear and ignorance, not out of actual understanding of how atheists behave. If it were proven that atheists in general had a strong tendency to immorality, then there might be some genuine basis for that mistrust, but this isn't the case. In modern times we have come to learn that a large part of human nature slants us towards cooperation and compassion -- I heard a talk on NPR recently in which there was a study showing that "giving" activates the same pleasure centers as sex does -- because generosity gives us a survival advantage. We are programmed to be social, caring creatures. This has nothing to do with belief or disbelief in retributional cosmic orders or higher powers (and a retributional cosmic order *is* a higher power, though we may not define it as a God -- maybe that's what you're meaning with "atheist"?).
I understand that the Buddhavacana describes materialists as those holding frighteningly wrong view because it should lead to immoral action, but the evidence of modern times (and my personal knowledge of many atheists -- though I am not one of them, being agnostic) is that this is not a problem in evidence. As was pointed out upthread, there are undoubtedly examples of atheists who are disturbed personalities who use materialism as the basis for doing bad things, but they are atypical and can't be used to judge the rest, just as religious extremists who fly planes into buildings should not be used to judge religious people in general.
In the end, what is important about rebirth is that it should motivate people to behave in moral ways, but the atheists I've met who are also Secular Buddhists are already motivated to behave in moral ways. They spend a great deal of their time considering the Buddha's teachings, putting it into practice on the cushion and off, and seeing great improvement in their lives -- for themselves and those whose lives they touch -- through the practice. This motivates them -- strongly -- to keep practicing, to study more, learn more, share more, to strive on unceasingly.
I would think you would welcome such practitioners as kindred. And more, have faith that if your understanding of what the Buddha taught is accurate -- in both senses, as an accurate understanding of what he taught, and something that proves to be factually true in the cosmos -- then you would be glad folks had stepped on the path in whatever place they start from, because you can expect the truth will reveal itself in time -- if not in this lifetime, then in the next or in a later one.