Store Sales banners will always display, no matter if you ignored the game/dev/publisher.
All that "ignore" does is that those titles wont show up in search results, thats it.
Steam would need to make thousands of different sales banners to account for all users different settings, i doubt they would ever consider that.

The Store's front page is not completely curated per user. If it were, the servers would crumble trying to serve up the millions of customized front pages for everyone.