I feel that most businesses have rather sexist practices. But it is for business reasons, not sexism. Sex sells, and everyone knows it. I am actually an exception at my job, since I normally work on a register. And that is usually a job done by women, but guys often seem to be rather fine coming to my register and trying to be all 'buddy buddy' if you understand what I mean. Women often can manage to get bigger tips, and sell to men better. For obvious reasons.
Not to mention where I work most of the women hate having to do the more 'male' jobs, because they require heavy lifting and moving boxes moderate distances.
As for pizza deliveries, how often have you gotten pizza delivered, now how often has the delivery person been a woman. With me it's maybe an average of 1 out of 50 my entire life. It can be a dangerous job, and more so for women. After all, as my mom put it when my sister started working at a pizza place, you are walking up to a strangers door.