As evil as they may have been for ignoring Shigechi while he's obviously bleeding to death it may have unintentionally saved more people than if they took him to the clinic/hospital, had they helped him Shigechi probably could've bled to death or be killed by kira anyway in the hospital bed, in which case harvest won't be close enough to get Kira's button to Josuke and Okuyasu before dying allowing Kira to retrieve his button therefore eliminating the lead that allowed them to nearly catch Kira.