So much piousness and moral judgment and internalised misogyny! I read this as if you like chocolate you're one of the laydeez- you need it for your time of the month - you're a lightweight frothy person with no restraint!
If you can't even stomach the sugar in a grape (better yet you only like blue cheese), you're a serious, sophisticated skinny restrained - French seeming - women!
So much snobbery and judgment in food - it's a feminist issue!
It is a feminist issue, but there's another related question that's missing in your post:
Why do so many women have treat mentality in the first place?
Seriously, a biscuit is neither moral nor immoral.
As part of a healthy, balanced diet there's absolutely nothing wrong it with eating a biscuit or not eating a biscuit, depending on your preferences.
If someone wants a biscuit, just eat it and enjoy it.
Get past the whole "ooh I'm naughty me having a little treat, it's been a busy morning so I'm going to treat myself to a cake... Long day? Of course I'll treat myself to some chocolate. Why wouldn't I?"
Common sense also works the other way as well though. If someone's eating a lot of 'treat' food such as cakes, biscuits, chocolate, rewarding themselves with food and then is overweight or unhappy with their appearance, noting that there's several hundred calories a day in treat food is probably a good place to make changes.