I'm not familiar with that particular hub, and I don't work on enough different bikes these days to stay up on all the stuff as it comes out. But as far as I know, the only reason the ends of the axle would be turned down is because the axle was oversize compared to class 9mm front axles, and needed to be turned to fit the dropouts. (if they turned down a standard front axle it would be too small and not fit the dropout correctly).
That might explain why they turned down the axle's ends. As far as to why they work loose, that's probably related to abandoning the wisdom accumulated over the last century, deciding that keyed washers are unnecessary and saving a few cents by doing without. IME hubs, pedals and headsets using keyed washers generally keep their adjustments, those without don't.
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