Everything I'm about to say is an overgeneralization. Keep that in mind!
But even before I started CrossFit, I was at a pretty social gym. The trainers would walk around and chat with everyone. It's their JOB to be in good physical condition (eye candy, hello). And these guys, at this specific gym, were KNOWN for philandering. (And I went on dates with a couple. One guy asked if I wanted to come over to his place after and watch porn with him ... so yeah, dream guys basically).
Even friends that work out at LA Fitness stay far away from personal trainers. They're "known" to jump around from female to female over the generic population of males. They are in peak physical condition. They have access to TONS of people. These people are, for the most part, wearing skimpy outfits.
And a coworker has worked out at muay thai (? cant spell) and boxing gyms. You have these smaller class sizes. And the coaches are touching these women, getting their bodies in the right position (for the exercise ... I honestly dont mean that in a nasty way). When you go throughout your day to day, how often do people physically touch you? Not many. And in a gym, it can be a great thing when you're getting physically corrected. That happens more so in those smaller type training settings.
Anyways, at this boxing gym, the trainers are making like $20-30/class. Barely making it. Their job of physical fitness is not really "paying" off. And then you get these lulu mamas there who look fucking great for 40. They're at the gym around noon-time. Which is slow anyways for you. And they start talking about how boring their humdrum life is. And you, as this trainer, are eyeballing their every movement, looking to make that verbal correction over poor form. And this woman has great form. And there's this guy just looking at her every move. "Paying attention" to her ....
I mean, yeah, I can definitely see crushes happening.
Sorry to get so "ranty". But Im a yoga instructor and I've been in that business of being in a position of knowledge and, in a weird way, power. As an instructor, people can unfairly "idolize" you. You dont really deserve it. And they can confuse that admiration for something different (this happened in the yoga community with John Friend. He was making bank of Anusara yoga and, boom, found out he was cheating with all these students ... and he lost everything). So I think if you're a trainer of some type and you dont realize you have this unfair advantage over your clients, it can give you a big head and lead you to make some bad decisions.