The big bang is an utterly simple concept- it's observable that the Universe appears to be expanding, and the rate of that expansion can be measured. So, extrapolating backwards in time, we come to a "time" when the Universe had zero volume- a singularity. It's not a creation myth, it's a description of the time before which physics doesn't work.

With a bit of luck, studying particle physics at energies comparable to those prevalent a few milliseconds after the extrapolated singularity, we may find that the equations don't work- that the whole current basis of physics is wrong. Because that's what scientists REALLY wanrt to happen. Not just because, once everything is found out, they are out of a job and there will be no more Nobel prizes, but because getting another layer off the onion is exciting, and opens up whole new fields of science.

And practical spinoffs are not only possible but probable- and they could be crucial, like allowing us to control nuclear fusion, which is probably the only hope for saving humanity from malthusian catastrophe.