I’m wondering about this one too – and I noticed it was one that wasn’t answered in the OP’s followup posting.
I suppose I’m coming at this from a slightly different angle – being that I am myself a housewife and have been for 20 years. Furthermore, I am not an especially ambitious, competitive or high-powered person. And, yet, I think I’ve made a valuable contribution to my family over the past 20 years. “Valuable” I say, just not in a financial sense. My husband is a very ambitious person – very competitive and very driven. He has been able to make his career his main priority on a day-to-day basis because I’ve been home taking care of the nuts-and-bolts business of running our home. And I assure you that my husband feels his luck – he has known many couples where both husband and wife have high-powered careers and, in general, their homelives are not as comfortable as ours is.
Your daughter seems to recognize (like my husband) the benefit to a hard-working career person of having a stay-at-home partner to manage the home front. If her intended is a good guy, his presence in her life could add greatly to your daughter’s comfort, if not to her bank account.
Now, the possiblity exists that he is not a good guy – that’s he is, in fact, a lazy slacker looking for a gravy train. But that’s far from the only possibility. The fact that he’s had a successful stint in the military speaks well for him, IMO, anyway. So does the fact that your daughter, a bright woman apparently, loves him. My advice would be to take a step back and give your daughter (an adult professional, after all) the respect of allowing her to make her own reasonable choices.