I can't get where is the Content->Article->ArticleFrontPage options you are mentioning in your question.
Regarding the front-end display:
- Is this happening to a certain menu item? article?
Note that Global Article Options can be overriden by menu item or article settings.
Each article has its own Show Icons settings in its Options Tab.
Following any of the articles menu items have the same settings in their Options tab.
So, I would suggest you to have a look at corresponding articles, menu items options, for which you still see the icons in the front-end.
Hierarcy
As regarding the hierarchy of the options:
Global Settings come first, Article settings will override the Globals, Category settings come next and Menu Item settings are last.
So a Menu Item's settings will override everything.
Template Overrides
As a last note: if changing settings doesn't seem to result to a change in the front-end, it can be due to template overrides. You might have a template that is overriding the layout output of the com_content component. So it's worth checking in the html folder of your template for a possible override.
More reading:
There is another similar question in JSE:
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Template overrides