People on HN work in ever more prestigious and/or difficult to get in companies that this.
Sure. But any other motive for doing such a thing is probably less smart too.
Not to mention that such a choice most likely satisfies passion and honor within a person.
If you are saying that any person that satisfies his passions and honor is considered smart, or that a person that works in something that gives him satisfaction is considered smart, then you are just twisting the definition of smart.
The hardest part of training is building up your level, but once you're there you keep it. I'm a sedentary 31 year old now, but I bet I could still pass the basic test at optimum levels, with a couple months training. I certainly won't be motivated to do the next stages though.
http://www.sealswcc.com/navy-seals-buds-training-stages-over...
I think you really underestimate the barrier to entry into the SEALs, and how that correlates to what the OC was trying to portray with his comparison.