For interest's sake, go Google: consumers don't buy farmed salmon.
This is the link that comes up: https://www.google.ca/#q=consumers+don%27t+buy+farmed+salmon&hl=en&prmd=imvns&ei=gcB3T_iPBuiKiALym5GnDg&start=50&sa=N&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.,cf.osb&fp=bd3320c5af24bc29&biw=1012&bih=531.
I scrolled through the list of pages and stopped at page 52 - Google was offering still more; this means that consumers are well aware of the environmental and chemical issues with farmed salmon.