Agree. It doesn't feel right to dance the Rhumba to Rumba or Bolero music. The problem is, with most Bolero music and a lot of Rumba music the bass pattern is typically half note-quarter-quarter in a 4/4 measure of music, giving it that distinct slow-quick-quick sound.
Most DJ's don't know or care about the difference. You can try asking. I have never had success asking. I just end up dancing the Bolero