Who is there for a day?

Yoma page 18 page 2:
Rav, who is a gunner for Darshish, proclaims from where he is to the day. Rav Nachman, who is a gunner for Shekantziv, proclaims from where he is to the day. And the Tanawi, Rabbi Eliezer ben Yaakov, says: A man should not marry a woman in this country and go and marry a woman in another country, lest they intermarry with each other and a brother is found marrying his sister (and a father marrying his daughter) and the whole world is filled with incest. And it is said about this (Leviticus 19:29), "And the land is filled with lewdness," says the Rabbis, "It is not easy for him to marry her, and he said, "Rava, you must demand that she marry him, and she must be reconciled, and she must sit down with seven clean women." The Rabbis, who are aware of him, are the predecessors and transmitters of the law, and there is no problem with a mother who is unique to him, since he is not similar to someone who has a piece of bread in his bread.
A. Is there nothing wrong with such behavior, which is really close to prostitution?
on. Is it possible to behave like this today?