Yeah. They will bully people who are by themselves because they are easier to bully, rather than trying to bully someone in a crowd. It's a power thing. They can control the situation more when they are bullying one person as opposed to trying to bully someone in a crowd. Even if that bully has a crony or two, they can bully someone who is hanging out with 5 or 6 or 7 friends because he's outnumbered. Basically, there is safety in numbers.
Some bullied people deserve it because they are bullies or on the path of becoming a bully. Nonetheless, the motive for bullying the bullies isn't always a good one. Even in those situations, the bullies get off on superiority and power etc..
Of course, there could also literally be situations where people are bullied who didn't have it coming, but I think it's the minority of cases.