Are there published stats you're referencing?
But perhaps the same reluctance to acknowledge those who seek homosexual relationships is present in people who call themselves gay, they won't acknowledge people as bi? Which seems like hypocritical bias against people whose behaviours are bisexual.
Maybe the behaviour you call out is because people want to have homosexual sex without being 'gay'. By which I mean without making that sexual activity the focus of their identity (I believe it's known as MSM)? It need not have anything particularly to do with societal disapproval.
Who one has sex with, and defining oneself by ones sexuality are quite distinct, as too are sexual desire and desire for relationships.
I'm interested in your response?
Young people sometimes use the word "gay" to express a complex sexuality which doesn't categorise neatly with a label. It's understood that you can be both "gay" and "bi" simultaneously, or indeed you can be a man who has sex with men who is straight.
The only person in this chat who is trying to put strict labels based on behaviour is you (the other commenter only observed some behaviour without labelling), so it seems like you're arguing with yourself?