First, Rome at its' zenith was the most openly mulit-religious place in the world until the modern age. People shopped for religions more than they followed them. You went to the temple cult, or the mystery cult that would help you the most with the specific problem you were having.
Yeah, and wasn't Elagabalus killed for those very things? When he was 18? After 5 marriages, including one to a vestal virgin? After prostituting himself in the Imperial Palace as well as out in public? The great modern historian of Rome, Edward Gibbon, said that he "abandoned himself to the grossest pleasures and ungoverned fury." While Neibuhr settled for calling him out on his "unspeakably disgusting life." And, exactly because of that decadence he was killed along with his mother, both by having their heads cut off and then the bodies were stripped naked, dragged all over the city, with the mother's body cast aside somewhere or other, while Elagabalus headless corpse was tossed into the Tiber.
You can do better than pointing to the Roman Emperors, my favorite, Emperor Caligula tried to make his horse a consul (he didn't, settling on making the horse a priest instead - take that for what you will, but saying that a ->-bleeped-<- was a priest or priestess puts them on the same level as Caligula's horse) in one of the interludes when he wasn't boinking his sisters, Agrippina, Drusilla and Livilla. (Several Roman Emperors showed a special fondness for sexing up their sisters, and on occasion, mom too - family values I guess.) Well, until his own guards killed him that is.
But of course most of that for either of them could have been made-up after the fact to justify killing them. It's hard to say.