Why?
This is well documented and has been known for many-many years.
There have been numerous, independent, studies on this. And it is real.
Men also have a physical response to seeing two men engaged in affection.
Men actually had MORE of a physical/stress related response to seeing two men kiss than seeing video and images of maggots crawling on spoiled meat, vomiting etc.
Measuring levels of salivary alpha-amylase, a digestive enzyme that is associated with stress and is especially responsive to disgust, allowed the researchers to examine the men’s physiological reaction to the photos. The study was based on results from 120 heterosexual men (aged 18 to 45).
“In comparing the salivary alpha-amylase responses of participants to the various slideshows, we found that participants had higher salivary alpha-amylase responses to the images of two men kissing and the disgusting images. In both cases, these responses were significantly different than the responses they had to the neutral stimuli.”
It is pretty simple biology based on evolutionary response. Men have very high sex drives. And it is imperative to the survival of the species that men do not engage in sex with each other.
Think about it. If men had the same sexual attraction to men as women... what man would want to mess with a woman?? We would all be gay!