Further on Superman as Clark Kent - who invited his adoptive Earth parents? Superman's funeral would be a world-class event, with only limited attendance inside the chapel during the actual service. Not only superheroes but dignitaries, Presidents, etc., from across the world would be present and expect to be among those given the limited seating. Short of revealing that they're Clark's adopted parents, how the heck would the Kents get seated near the front row? And even if Bruce Wayne pulled some strings, wouldn't that raise suspicions that they had some connection to Superman? That, along with Clark's absence (see above) would seem to permanently blow Superman's secret ID.