Piracy harms all software publishers, regardless of their size. Software publishers spend years developing software for the public to use. A portion of every dollar spent in purchasing original software is funneled back into research and development so that better, more advanced software products can be produced. When you purchase pirated software, your money goes directly into the pockets of software pirates instead.
Software piracy also harms the local and national economies. Fewer legitimate software sales result in lost tax revenue and decreased employment. Software piracy greatly hinders the development of local software communities. If software publishers cannot sell their products in the legitimate market, they have no incentive to continue developing programs. Many software publishers won't enter markets where the piracy rates are too high, because they will not be able to recover their development costs.