Lots. Lots of people enjoy music for its own sake. Just like some people like dancing as an art, and painting and acting... Not everyone is shallow and a worshiper of the cult of celebrity.
Mariah Carey, Whitney Houston, that dreary French Canadian woman all sell out worldwide but aren't known for their sparkling personalities. It doesn't matter - COS THEY CAN SING.
Few people gives a toss when they go to see Carlos Acosta what he is like as a person either. And people were not put of seeing Michael Jackson by the trials and the rumours - because we was a world class talent. Ditto Darcey Bussel, Tom Cruise...
Personality can make a career but talent can too and sometimes a person has both.