Personally I don’t see why we wouldn’t. We are animals after all and similar to many mammals that do indeed have pheromone systems. I feel some people consider the thought of pheromones to be unhygienic, beastly or primitive and so tend to reject the notion on that basis alone which lacks solid reasoning.

Having said that there are also several scientific approaches that both propose and condemn the idea.
Some thoughts for you:
Human olfaction is comparatively poor compared to the smell capabilities of many other mammals - dogs for example have 40,000 times more sensitive noses.

Humans use soaps, body lotions, colognes and perfumes etc which are so potent and aromatic that one would imagine they make pheromones, if we have any, redundant.

Olfactory nostalgia is a powerful memory aid. Key memories, emotions, places and things can be invoked in the mind of someone smelling a certain smell. Perhaps a significant others sweat or natural body odour can be enmeshed with the emotions of desire and affection in the same way?

Pheromones in other animals act at relatively long distances for an extended period of time. People generally don’t get close enough to one another and perhaps mix too quickly in large crowds and social groups for there to be any effectiveness of such chemical messages. Coffee, cigarette smoke and other scents in the human social setting may completely overwhelm subtle signals.

A small handful of experiments suggest men find women's body odour more attractive during ovulation.

MHC class molecules of the immune system are often secretory - many end up in sweat glands. The olfactory system has the capacity to bind with several parts of these molecules (in theory). Their volatility in sweat however is questionable.

Humans sweat during sex. They also kiss. It would be easy for pheromones to be produced only during arousal in body fluids or as a bonding aid. Arousal is a difficult thing to establish in a clinical experimental setting with onlookers.

Finally... wealth, physical attractiveness, personality, career etc all influence the choices we make about partners so pheromones may be obsolete due to cultural and societal values.

Thoughts?