Some people think good quality tone controls are good if you use it to correct any "problems" in the bass, midrange, or treble.
Room EQ is a form of tone controls to me. The idea is to fix nulls and acoustic issues in the room.
However, I've never had any luck with Tone Control or Room EQ.
Oh, wait, are you talking about Tones directly & physically on the speakers and not in the pre-pro?
In most cases, they are good because they allow more flexibility. In a lot of cases, they affect (increase/decrease) both Bass & Treble (Salon2, Orion, KEF Reference). But in some cases (Philharmonic speakers), they only affect (increase/decrease) the treble.