Er, guys? Hairless breeds still produce dander. And considering they're somewhat prone to skin issues, some of them produce more of it. And in cats, it's not even just dander that's the main allergen. Though I haven't a reference handy, I've seen it suggested that proteins in the oils of their skin and/or in their saliva are to blame for most allergies. Yes, lacking hair means that these allergens are less likely to build up on the animal, but is it really better to have them shed it all over your house?
Regardless, the breeds of animals most commonly accepted as somewhat hypoallergenic are those with curly coats. For dogs, this means breeds like the poodle; for cats, it's the rex breeds. No, I haven't the slightest idea the mechanism behind this, and yes, some people do still have averse reaction to even these breeds.
As for the original topic of this thread, certainly. The presence of an ally is appreciated as stated by others above, but there's also the fact that I'm actually better at interpreting their body language than most humans. It's a confidence booster, having people look to you for guidance. And it's certainly nice to have someone ELSE acting the social ret*d for once!