eh... although every woman is nuts and has baggage, i don't try to overthink shit like that. Again, you should know what type of person you are involved with within the first year, certainly before you ask their hand in marriage.
But to your point, if your woman had sex for reasons like that when she was young and hadn't really matured, or found the right person to marry, is that going to deter you from marrying her? Unless she is a black widow, who cares if she fucked dudes to fit in? Or because she was pressured (like 99% of most girls that age).
What I'm getting at is why ask in the first place? If the girl is perfect for you, loyal, loving, and whatever else you require, what does it matter?
i think the majority of guys feel they NEED to know this is because traditionally men have fragile egos and if they hear that their woman has had what they think is alot of sexual partners, or god forbid more than them, they feel threatened. Same reason why men are worse at casual sex than women (on the whole). Men need their egos stroked constantly and can't feel as if their partner is "better" than them at anything.
Again, this is my take. I think of myself as a little different than most men when it comes to this, and sex in general. I could just never see the point in it being a conversation. All it does is cause a bunch of bad feelings that you would never have in the first place if you could just let it go and focus on important shit. Yes, sex is important, very actually, but IMO not in this regard.
I could have sat all day and worried about how many dudes my wife was with before we got married, but i chose to focus on how wonderfully loyal she was, how amazing she made me feel when i was or wasn't with her, and how I wanted to spend the rest of my life with her.
The fact that she's an absolute freak just made it better. So I say thanks to any of the dudes (or chicks. lol) who showed her any of her tricks...
Cause I get to enjoy them forever!!!