There are no answers to these questions: only opinions.
A dancers attitude to his or her partner, surely, depends on WHY they are dancing together. If I dance with my own spouse, or someone with whom I have an emotional involvement, then our dance is an expression of our relationship: and particularly in the Latin dances, all that eye contact, and seductive movement is for real - all perfectly proper, and it underpins and informs our dancing.
However, if I switch partners, and dance with anyone else, then unless by mutual consent, a non-dance relationship is developing and welcome, then exactly the same physical responses to each other are play-acting. If you like, this is playful and non-sexual flirtation. I can happily dance with ten partners in an hour, and feel nothing whatever for any of them. Except at the highest levels of dance performance, you shouldn't see any difference: but MY attitute to my partner is fundamentally different from that with my OWN partner. You see?
The primary consideration here is courtesy: we dance together because we enjoy partner dancing. We might also be looking for a partner on a different basis, and if one's attentions in that area are reciprocated and welcome, then the happy situation exists where all our requirements are met in one relationship.
Some of the cavorting of latin competitive dances looks, frankly, as though it would be more at home in a brothel. Each to their own, I suppose.