I'm no saint. I'm sure I've done my share of hurting people over the years. We're all quite selfish and I don't think that's so bad really (I actually learned that from Ayn Rand without becoming a Shruggalo). But there's a big difference between looking out for number one and actively cheering on the suffering of others for no reason at all. Also, too, being complicit in directly causing that suffering just for giggles.
People are assholes.