Your thought process involving the process and topic is very understandable. In my humble opinion it is mostly pure human instinct. Especially true, of our current society norms.
No reason to be embarrassed. If it goes on inside the confines of a bedroom with consenting adults, then it would be fine with me. Sometimes, we have to leave our thoughts at the door.
As indicated, thinking back, I'm actually embarrassed (even mortified) over the experience. Curiously, I've discovered some gay or bisex videos featuring porn kings whom I thought were straight. Peter North; John (Johnny Wadd) Holmes; and more recently, Charlie Dean from Europe.