Do you know why?
Why, yes I do. You can read about it here and I'll briefly summarize: the nature of earth's early atmosphere is hardly a settled issue--nor is the location of the site of early life's start. It might not have been in the atmosphere, it might have been at the mid-ocean vents--and even if it is reducing, that doesn't particularly obviate the main point of the Urey-Miller experiment: that it's not very hard to get some amino acids by giving a puddle of carbon sludge a good fierce jolt.
You started this discussion by calling the Urey-Miller experiment fraudulant. Offhand, I'd call that intemperate slander.
Please donh, I didn't think even you would bring up the silly vent origins hypothesis. Oy'