The first few pages of the satanic bible go like "Most people think satanists are teenagers that dress black, listen to rowdy music and burn churches down (basically edgy, yeah), though those people may not be called real satanists", ykno, Satanism is called Satanism because it should resolve arround yourself and not some God. Its also called that to scare off some of the people who doubt the religion so your daily satanist doesn't have to deal with them.

What actual benefit comes from worshipping any symbol, like any other such as god?

Though, there is no worshipping anyone or anything in satanism (not even in rituals lol m8). Funny thing is that you said "of all that is evil in the world", basically satanism labels you, yourself, the human being as the devil, basically because "While good an evil don't exist - except within the bounds of personal preference and perception,".
So if you're gonna worship someone youre going to worship yourself, which kinda sounds weird.

Man we are derailing this thread guys.

EDIT: did u rly have to add the white text after I posted my response DUDE