This is more of a personal thing and because of the fact that the airlines depend on you being reasonable intelligent as far as getting to the airport on the correct day. I was in South East Asia and was departing from Singapore. It is quite common for these cheaper flights to the United States from Asia to be red-eye flights or at least flights that depart at really silly times on the middle of the night.
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Back in those days Singapore still had one of those cool flight information boards that manually flipped letters.. That was really cool actually
For me, at that point in my life having just exited college a few years prior, dates didn't change in my head when the clock struck midnight, which of course we all know is exactly what happens. However, this didn't register in my mind and while I realize there are only a special group of people that wouldn't double and triple check their flight details especially on a long haul flight like one that is trans-pacific but on that particular day I was that guy.
I don't remember exactly what day it was but the ticket said something along the lines of 19-mar 00:15 for the departure time.
So me, still being in college mode, turned up on what inside my brain was the 19th and quarter past midnight but it was in-fact already the 20th and my flight was long gone.
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So this was back in the times when a ticket purchased months ahead of time was dramatically cheaper than a last-minute one. For the most part, that notion has disappeared but back then, I was forced to buy a last minute $1200 ticket. My original ticket was something I had purchased many months prior and the total cost was less than $1000. Now I found myself in a situation where I was spending more than that for a one-way ticket. If I had any sense I would have at least looked into how much return tickets were because back in those days, often a return flight would be cheaper or at least the same price as a one-way ticket for reasons I can not understand.
This probably doesn't apply to most people but we have all had our dumb moments in life. This was one of the dumbest ones in my life and it ended up costing me what at that point in my life was TON of money. Hell, $1200 is still a lot of money to me today.
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So don't be a moron like I was and yeah, I bet most people wouldn't be anyway but I suspect this is why no flights ever depart at 00:00 because half the people would miss the flight because what day is that?