But why do you think that this is gay? Don't get me wrong, I am not so much disagreeing with you, I am just personaly not very fond of classification when it comes to sexuality, where this is gay and this is straigth, those are just labels. Sexuality, is one of the most complex characteristisc of humans. Kinsey, what ever if you want to believe him or not, estimated that around 90% of the population has bisexual preferences. And I am inclined to agree with that assesement, as almost every male can judge the look of another male - or his own! And where most females can also tell you if another one looks good or not. I probably go out on a limb here, when I say that I would even argue that this might even have an evolutionary reason. A male or female that can judge what the other sex finds attactive, might have more succes in finding a potential partner. But that is just pure speculation, so of course not more then just a thought. But there is no doubt that most people have a sense of aesthetics where we simply 'know' what looks healthy and what not.
But homoerotism, for example, where a male finds certain male atributes very appealing, doesn't have to lead necessarily to gay relationships. History in particular, is full of such relationships, where males - and females, share intimacy with each other, without engaging directly in a sexual intercource, with their genitals. Today, of course the kissing of two males, expecially on sensible areas like the neck, is seen as strongly homosexual. But if that HAS to be a necessarily a sign of homosexualty? I don't know.
For example, you would be surprised how many homosexual men out there find certain female attributes very attractive, without actually seeking a female relationship or even sex. Up to the point where they would even find the idea of touching or kissing a female, or certain parts of her body arrousing.