On first dates women should pay for their own drinks and meals

It's like window shopping, there are no means of knowing if this girl is a opportunist or just wants to "fill in the gap" for the evening using you or are just plain broke and need some wine and also there are no guarantees that you will like this girl and neither do you know if they are sincere so... they should pay their way on first dates. Or at least sign an "IOU -if-not" beforehand.