Very, very few manufacturers include USB cables with their printers.  Essentially, it's a gift to the retailers that carry their products, since they can then sell you a cable with a 500% markup (and I'm not kidding).  Thankfully, Dollarama and other dollar stores now carry USB cables pretty regularly, and they work just fine.  
 
Never, ever buy a cable at a place like FutureShop or Staples.  If you need something a little bit more specialized, then it's far cheaper to order it online (at a place like 
http://www.monoprice.com, for example, which carries cables of all types, including the usually pricey A/V ones like HDMI).  Alternately, places like TigerDirect or Canada Computers tend to be a bit cheaper than the big chains.
 
If you happen to have a friend that works at FutureShop or Best Buy, you could also ask them to pick one up for you with their employee discount.  You'll find that the $25 USB cable they sell to regular schmucks can be had by employees for about $4 (which is their cost price + 10%).