There is nothing commercial about prog rock music.
There were a number of 60's/70's prog rock bands that sold a lot of records and were on the radio regularly...so, I tend to think commercial is a pretty relative term. There is also lots of disagreement about what bands qualify as progressive rock so making a list is always asking for a hard time.
King Crimson, Yes, Genesis, Pink Floyd, Jethro Tull, ELP, Supertramp, Kansas, Rush all sold plenty of records and got plenty of airplay, so I think progressive rock can be very commercial in some cases and not in others (like Zappa).
