It depends on the species of labyrinths, (gourami or betta). Some species are peaceful others are agro.
Blue, gold, kissing & giant gouramis are pretty agro, whereas dwarf, pearl, snakeskin and moonlight (silver) gouramis are very peaceful. Betta splendens is agro but Betta imbellis is peaceful.
Male labyrinths are all territorial to some degree but many will simply chase each other around a tank. In a very small tank without much cover, the dominant male usually stresses the weaker male and eventually the weaker fish succumbs to a disease.
In a shop gouramis are kept in groups. Often there is 20 or 30 fish in each tank and any aggression is spread out over all the individuals. In a home aquarium the aggression is directed at any other fish in the tank, but generally other male labyrinths bear the brunt of it.
Shop tanks are also overcrowded and the fish are fed sparingly. This means the fish are not in good physical condition and as such are less inclined to breeding and more interested in just surviving. When you get the fish home and feed them up, the fish start to act more naturally and that is when territorial disputes arise, (if they are going to).