I would severely doubt that a quarter of all fish stocked by lfs are hybrids. Furthermore, I can guarentee that only one of my fish is likely to be a hybrid, and that is the sailfin plec due to the fact that a number of species hybridise in the wild, and not the sort of hybrid being talked about above. Most of the members on here I talk to are very unlikely to house a hybrid as well. I would love to know on what evidential basis you are making the above claims.
And why wouoldn't we include marine fish in a tropical fish forum? I'm pretty sure all the marine fish listed have a temp range of 20-26 degrees C, putting them as tropical (unless someone has recently added a profile for cod?). Remember, tropical only relates to temperature.