Heavy Metal is not necessarily satanistic, it is a music style, which has many many subgenres and which fans share a certain set of values (for example being no bourgeois, friendship, freedom, individualism, no bowing down of your person for commercial success, patriarchal role model (^^) ...).
Playing around with satanistic symbols outside of Black metal is in most cases pure provocation of the "good people/bourgeois" and no real satanistic belief, as most metals heads i know are atheists or agnostics and outside of christian belief there is no room for a devil as counterpart of god.
Ozzy makes good music, if he privately kneel down to pray to god, why not? Its his private business, i must not follow him and i don't excommunicate him because he is a christian.^^
I guess i'm now more bourgeois than in my youth.
As long as i don't become a 100 % caricature of a bourgeois, everything is fine.
Edit: Personally i wear a celtic cross without being christian, more like my faible for ancient celtic culture / paganism although - if i'm honest to myself i'm more agnostic.^^