[saraid216]

Loudly sneezing, blurring your vision, and ruining your sense of smell are really not conducive to surviving an encounter with a big cat.

I mean, you might piss it off if you sneeze on it, I guess. Yay?

[jccooper]

It's an environmental allergy, not an emergency one. If you notice you feel like crap in a certain place (because cats like to lurk there), and subsequently avoid it, that's a win.

Not that I necessarily believe that's a good explanation for allergies, but it's plausible enough to think about.

[chaosfactor]

Costs vs benefits.