[Probably NSFW] Why is there a correlation between high heeled shoes and sex scenes in movies?

I have observed this – not just in porn, but in mainstream movies as well (usually rated R).

It seems like high heeled shoes are the indicator of sex to come. The women with the highest heels generally are the first ones to jump into bed.

Worse yet, in some films, the women keep their high heels on – even if everything else is off.

How and why are high heeled shoes so connected with film sex?