I know in U.S. there are so many liquor ad posters with hot women. But especially in South Korea, famous Korean actresses actively appear in so many kinds of liquor advertisements as pictures above. Every time when new brand of liquor comes up, the advertisement poster comes up with the new hot female stars. So, many people say that 'if you want to know who is a popular female star recently, then look at liquor ad posters.' Also, we can notice that the concept of the stars is 'sexy' or 'attractive,' which is enough to grab an attention of the public especially of men.
The purpose of the poster can be just grabbing attention. However, I think this is a classic example of 'classical conditioning'. There's a clue for it. In the posters, actually the size of the liquor is much smaller than the picture of women even though the object for advertising is liquor. Also, the body posture of the women, the facial expression of the women, or cloth of the women is very tempting (tempting men). In terms of the principle of classical conditioning, tempting body posture and the facial expression of the women make men to feel excited or feel good. So when the men have a chance to drink, they can recall the picture of female stars and their feeling of the time then they choose the certain kind of liquor. So easy to say, model of the product makes public to choose the liquor rather than merely the characteristics of the product.