Don't you think it's a bit irritating to hear a 'bless you' every time you sneeze? It's not polite, it's annoying. My snot and I don't need to be acknowledged and my 'soul' is not attempting to escape so stop blessing me as if you're some priest on speed.
I suffer from sever allergies and in the summer, spring, fall, basically anytime that's not winter I suffer from the most insane sneeze attacks. Like 10-15 sneezes in a row, and to have someone continuously bless you is like jsut as painful as having to sneeze that many times. Especially when you bite your tongue/ cheek when you're trying to say thank you!
I try to say "bless you" to the people in my office if they sneeze. It's not a religious thing for me, but more of a polite thing to say. And there's only two of us here, three max so no "bless you" can make for an uncomfortable silence.