staff insights - what do your staff think?

So working for a company that have quite diverse staff and locations got me wondering why most companies including my own, dont use staff to help under stand what people want. Surely staff know what they want, but also understand how they can help ther company.
It is interesting that compaies dont make use of such a fantastic free resource. So what does your company do? Does it listen to staff, or really only listen to customers?