I can see an argument made to not allow tailored pheromones. It's not always a single negotiation, it's a series of them, and many of the people you're going to need to talk to won't be able or willing to meet you face to face. Honestly, in a world of things like tailored pheromones, mind control spells, and emotitoys (under 4th ed at least), it's frankly a miracle that ANY meet happens face to face rather than in a relatively controlled online environment.
However, for the sake of simplicity, they're fine. Just keep in mind the time it take to get items, and the restriction of one item (or group of the same items that you would naturally buy in bulk, like ammo) at a time.