Probably, yes. It's sometimes possible to keep two male Gourami together - I had a pair of blue males that lived together for about 6 years in total harmony, and I have a pair dwarf Gourmai now who get along okay, but they are in a very heavily planted tank where they can get away from each other and I'll separate them if they ever show signs of aggression.
With four, you're almost guaranteed to get at least one aggressive male. If I were you I'd take them back and tell the salesperson that 4 males can't exist together in the same tank, and they should have pointed it out to you. They should either let you return them or swap them. If you keep them you're almost certainly going to have a problem.