Well, Gaston isn’t really attracted to anyone but himself. He’s a classic narcissist, and his pursuit of Belle is purely to feed his ego. If he could have sex with himself, he would. Vigorously, and somehow selfishly.

Le Fou, on the other hand, is an effeminate sycophant. The live action explicitly makes him gay, but the animated version merely suggests it. Singing about how handsome and manly he is, and how much everybody wants to wrestle with Gaston with the biting and the spitting and the hair-covered inches.