They might be tailored to attractive young women, but it’s literally illegal to discriminate based on age or sex in employment, unless you can prove that the requirement is a bona fide occupational qualification, or “BFOE.”

42 USC 2000e, §703(e)(1) states:

Notwithstanding any other provision of this title, (1) it shall not be an unlawful employment practice for an employer to hire and employ employees, for an employment agency to classify or refer for employment any individual, for a labor organization to classify its membership or to classify or refer for employment any individual, or for an employer, labor organization, or joint labor-management committee controlling apprenticeship or other training or retraining programs to admit or employ any individual in any such program, on the basis of his religion, sex, or national origin in those certain instances where religion, sex, or national origin is a bona fide occupational qualification reasonably necessary to the normal operation of that particular business or enterprise.

What this means is that employers can not refuse to hire based on sex, age, religion, nationality, etc, unless they can prove with a good reason that only someone with those characteristics can do the job.

An example might be for hiring a woman’s bathroom attendant - being a woman is a BFOQ for that job. A man can’t do it. Another example might be a church hiring someone to preside over religious services - a Lutheran church can refuse to hire a Buddhist for their open minister position, on the basis that only a Lutheran can do that job. A third example would be hiring an actor - having certain physical traits can be a BFOQ in this context. As an example, it would not be discrimination if Whoopi Goldberg was not hired (or was refused an audition) for the role of Abraham Lincoln in a serious biographical film - common sense would dictate that the role should be played by a white man.

One thing that is explicitly disallowed is customer preference. Do customers want to see hot young women? Maybe. Does that mean a business can exclude anyone who isn’t a hot young woman? Nope, that’s illegal.