The icons are added to the feed per filter in modules/sharedaddy/sharing-service.php
:
add_filter( 'the_content', 'sharing_display', 19 );
sharing_display()
does check for is_feed()
, so there shouldn’t be a problem … seems to fail for no obvious reason.
You could add another check; something like this:
add_action( 'init', 'disable_sharedaddy_in_feed' );
function disable_sharedaddy_in_feed()
{
is_feed() and add_filter( 'sharing_show', '__return_false' );
}