Guilty Pleasures

I will never understand why women always shame or guilt themselves, especially with food. Like the whole world wasn’t enough, we also have to do this to ourselves.
I have overheard so many women, biting into a piece of chocolate or a beautiful cupcake, talking about how this is their one guilty pleasure, how they so rarely reward themselves with this treat, body shaming themselves while they are at it, for good measure.
The other night at Robertson Quay, I heard two women discussing sex with men who they don’t really like and how they always feel a bit guilty about it.
What does guilty pleasure even mean? Who came up with it?
Why should there be any guilt in what gives you pleasure?