Watch this and note that the Saudi host has no logical argument against the articulate Jihadi sitting in front of him. Once you accept the basic Wahabi ideology (which is really just classical Sunni Islam taken to its logical conclusions without compromise of any sort), it is very hard to see why the militant is wrong and the host is right.
Indian Islamist Zakir Naik is by no means unique in thinking grave worship is wrong. You do not have to be a wahabi to think that. But they do take it to its logical conclusion.
Logic is the enemy. Seriously.