You can if you want, block that nonsense from appearing in your browser by adding the following line to your 'hosts' file:
You may need to restart your browser and/or reload the page as well as clear the cache.
Note, that this blocks everything from content.betfair.com which is where the arcade stuff comes from. Instead, your browser may display something like 'Web page not found' in the section of your browser where this content appears. If this is an issue, or you like to get involved in the arcade games etc, then this fix will be a no deal for you. Instead, turn your volume down :)
For me, it's a deal. Job done!