Professional Amps are mostly used in home theatres when a dedicated audio processor is used. Some use professional amps when they need extra speakers in addition to the speakers connected to their AVR, like extra surround speakers or passive sub woofers.
There are different types of professional amps, like amps designed for PA (public address) systems, installed sound, Live sound, Studio, Cinema ect. Amps designed for cinema use would be great when used with large speakers like speakers from JBL pro series. But using pro amps for cinema use in a home theatre with a standard 5.1/7.1 set up with regular speakers would be an overkill.