DJ Yuca
Son Montuno
You are nitpicking, but indeed correct. Lots of chachachá in rock for example. But Azzey's right that you don't get the same "groove" or "feel" dancing salsa to other music. Watching the US finals of Dancing with the Stars the other day (not by choice) and it just looked and felt totally wrong for them to dance samba and chachacha to songs that were not samba or chachacha. The judges seemed to think it was intended as a challenge to dance to songs that have nothing to do with the dance genre, but to me it was just yuck. No groove just dancing choreography by numbers to some popular radio songs.
You're just jealous because there are no salsa to r&b nights where you live.
You could always move to the E Mids (UK).