bohm: To answer your question a briefly as possible: Science doesn't work that way. It is the venue of science to explain, via a verification process, that what we observe, believe or postulate is true. If we can't trust and abide by that method, then each of us is free to conclude anything we want.
The long answer to "why is that 'mere acceptance (scientific faith)' a good way to summarize that" is that, 1) I don't know. I'm simply stating that to me it makes sense that someone in-the-know would put it that way and that as a physicist, he's in a good position to questions our "mere acceptance" of physical laws. 2) It is indeed correct that we simply do not know yet. That's the very reason I tend to take Dawkins explanations with a grain of salt. The fundamentals aren't there yet. That doesn't mean there aren't any. But with our limited knowledge come limited answers. Any conclusions we make beyond what can be positively established is probably influenced by our own desire for it to be so.
For example: Dawkins suggests that one of the reasons individuals have a propensity towards "religion" is due to an innate sense of "trust", which is critical in the development of children. This, according to Dawkins, makes them "primed" for absorbing societal and religious teachings which can be manipulated by religion. He parallels this to the moth instinct for navigation by the light of the moon and stars which also cause it to fly into a burning fire. The problem is that, while the comparison is clever indeed, the known traits of moths' (and other species') navigation capabilities are clearly embedded in genetics while the same, at least the sense of "trust", cannot be plainly demonstrate genetically in humans.
His "misapplication" of such traits is what leads to negative results, like religion. He makes the same argument about "dualism". He says that we are all born "dualists" with the ability to think of "other", such as an imaginary playmate. That also sets us up for the "otherness" of religion. So to him, religion is a by-product of errors in specific "modules" that are misdirected. The problem is that this is contrary to his assertion that Natural Selection is "ruthlessly efficient". Above all, he describes no experiment via which this can be established.