How is it that Hollywood makes sin so attractive? Manipulation. Were they to be truly portray the effects of sin, we would see it for what it is and avoid it. There are cases where the consequences are true. "Requiem for a Dream" shows drug addiction destroying the lives of people as they go further down that dark hole. However, Hollywood with its sexual liberation uses all its tools of manipulation to make the audience accept, even applaud immorality. Since sexuality is closely linked with love for most people, it makes it easy to make sin seem like an act of love. Here's how the manipulation happens: 1) Ugliness verses Beauty. To make sin look enticing, the life a character comes out of must be ugly. For example, the spouse is less attractive, serious, and boring, while the "lover" is beautiful, fun, spontaneous, lively, full of the "joie-de-vive". The home environment is dull and colorless where the place of the affair is full of bright, vibrant colors. The audience is made to understand that leaving this confining, barren land to partake in a wild and free romantic affair is perfectly natural. 2) Tragedy. The characters embracing sin are tragic. They are are the sad victims of a dead-end job, a dead marriage, they have been oppressed in some way (culture, parents, boss). The tragedy has the audience believing that they deserve something good. 3) Reluctance. The characters are never allowed to rush into sin. They struggle to resist, but eventually get "caught up in the moment". By combining these three techniques, an audience is moved–manipulated–and feels a bond with the characters as they go about their sexual exploits.
[Other sins are so taken for granted that Hollywood doesn't even bother to make a case for them. Lying is standard, the norm even between people who are supposed to trust one another. Greed and covetousness are often motivating factors for plot lines.]