Your body is often sneezing because it has been hijacked by a virus that triggers the sneeze in order to spread infection.

Sneezes were evolved before the invention of the handkerchief and tissue.

Unless I inhaled pepper that never happens. I've watched others learn this technique too even large men. It can take years of practice though, just like learning any good habit/manner.

I think the question is if you've considered that not sneezing completely may encourage a situation where you sneeze more often. If the sneezing is actually a helpful thing, it might be a problem to inhibit it.

As someone with severe seasonal allergies, it certainly does happen to others. Its not about manners or habits for everyone.