Actually some do; most do not..
Like many, but not all, Roman Catholics worship Mary.. and other RCC "things"..
Some protestants worship the bible.. they deny it but they do..
Lots and lots of idolotry.. in both camps..
And many there is that deny it in both camps too..
Had to happen, as (the seven churchs in asia) in the book of revelation prophecys..
Mankind does seem to have this penchant for idolotry..
And inventing yarns about their idols..
Take the theory of Evolution for example..
Which in that case is a virtual assault on the Holy Spirit and man's spirit..
Making "science" the icon(idol)..
I'm not about defend Catholics since I'm not a Catholic, though I suspect some would refute your allegation that most worship Mary.