i know that some professional hockey players keep the same equipment for years because of how it fits. Obviously, we non-professional players keep it for years for other reasons (cost being one…). But the question remains, how do professional hockey players keep their equipment from smelling badly? What does one do?
bray
Not a lot seems to work, except airing it out when you aren’t playing. Don’t keep it cooped up in the bag.
It’s helpful if you have a storage or utility room in your house away from the rest of the abode, as some others in your home may not be as supportive of this practice.
You should wipe your stuff down with soapy water, too. You don’t want to get it so wet that it doesn’t air-dry easily, however.
Who said hockey players were supposed to smell nice, anyway?
Milo’s got it. I’m not sure if you actually play, or are just curious, but I’m writing this assuming you do. I let everything air dry outside. I’ve set up a line that hangs on my porch and when I get back from a game I hang everything on it. Except for what’s washable, of course. The worst smells tend to come from skates because of fungus and the like. Always remove the pads from the bottom of your skates and let them dry by themselves. Trust me, it makes a huge difference. But, eventually, it’s gonna stink anyway. Nobody in the room really notices because they all stink, too. 
Also, I’ve found that people who wear socks when they play have smellier feet than the rest of us. I highly recommend skating barefoot. It’s cleaner and gives you a better feel for the ice.
I have a pair of shoulder pads that nothing gets the mildew smell out of. I even soaked them in bleach water as a last resort. Drying stuff in the sun helps, but hockey equipment just smells bad. I lent a guy on my team a practice jersey that I can’t wear even to this day.
Make sure that your equipment is dry before you store it for any length of time.
The best story for equipment longevity is probably Craig Ludwig’s shinpads. He wore them throughout his college career and through a 16 or 17 year NHL career.
Then you smell the goaltenders pads – I can barely stand myself, I can’t see how anyone else can.