I'd say they're dumb then for not finding out and that it's their fault. They are investing themselves into a relationship and didn't understand how it would be? Their fault, which also is backed up by the fact that the average layperson is dumb.
If she worked so late that she was never home and didn't want to have any fun, I'd either deal with it or leave. I'm never going to complain though. There is literally nothing more negative for relationships than complaint in my opinion. It's like anthrax for your relationship I swear.
Listen, man. I like you. You generally seem to have some pretty solid opinions on whatever the latest topic of the hour is. And I completely understand where you are coming from and agree with you that, before entering something like a marriage/long-term relationship/whatever, both parties should make sure they have a general understanding of where things are headed in terms of life, careers, kids, finances, etc., and whatever else might go down. Also, couples should make an effort to really only make a deal out of things that matter, if at all - don't nitpick over every little thing that bugs you.
That said, life is unpredictable. Also, sometimes we don't always know the nitty gritty details of what's up ahead (e.g. being consistently woken up at 4:30 am, which, for most people, is an ungodly hour). On top of that, as much as people try to get things "figured out" before delving into a relationship, that just doesn't always happen. In reality, you are often times working things out as you go. And that's ok. Sure, get the big things figured out, but that doesn't mean that you eliminate all possible chances for conflict or disagreement in the future. People don't work that way. Relationships don't work that way. Stuff comes up, and you deal with it. Together.
That often means some form of compromise. And that's not always a sign of weakness or bitch-pampering that you seem to think it is. Sure, it can be. I don't know OP's situation, and as someone else mentioned above it's impossible to intuit the complexities of someone's marriage from a few lines on an online forum. Whipping out the "Well, this is what you signed up for" or "your schedule is more controllable and thus less important than mine" card is a quick ticket back to singledom. Which may be what you want, and that's OK.
To the OP: My wife is a lighter sleeper than I am as well. Additionally, our 4 month old is in our room with us right now. I downloaded an alarm app on my phone that gradually increases in volume (using a non-annoying sound - there are some pretty bad ones out there), but starts off quietly. I'm usually able to catch it before it gets loud enough to wake either of them. The trick then is not repeatedly hitting snooze....