From what I gathered; he was just a homeless man; and don't think he wanted to do any harm to them....I thought the idea of the purge was to release the beast and vent your anger out by even murdering to people who did wrong to you
shareThey were spoiled elitists who basically wanted him dead for one reason that involves Quentin Tarantino's supposed "favorite word." The way they refer to him throughout the whole film pretty much gives their racism away.
shareEarly on in the movie, when the purge gang show up at the Sandin's house, the leader mentions that the stranger killed one of them when they attempted to execute him
shareHe was black. That's why
shareOr he was homeless/poor, making him an "undesirable" in that society. Remember, one of the neighbors that tried to purge on the Sandin's was Black, so not all Blacks are prey.
And as a previous poster commented, he dared to fight back and actually kill one of the gang when they attempted purge on him.