Under no circumstance should a fan initiate contact with a professional athlete. They shouldn't throw beers, or paraphernalia, or do anything to cause harm to players that are just out there doing their job. These athletes are there for our entertainment, and just because you paid an arm and a leg to sit front row does not mean you have the right to touch the players.
With that said, this Browns fan was well within his rights to shove Jeremy Hill. He's actually lucky. 50/50 chance a die hard Browns fan in the Dawg Pound is carrying a switchblade. You want to leap in the crowd in your own stadium, that's one thing. However, if you do it in one of the most well known hostile environments in professional sports you are asking for whatever is coming your way.
The Browns finally had a glimmer of light this season only to see it washed away during the past three weeks. Their fans just had a glimpse of the future of their franchise. A person that was supposed to change the entire perception of what it means to be associated with the Cleveland Browns, and it was an abject failure. Not to say Johnny Football won't get better, but for now I would avoid jumping into a pit of frantic Browns fans. He could have celebrated like an asshole 3 inches from this guy's face and the guy would have to sit back and take it. However, once Hill leaves the playing surface and tries to jump into his seat he loses all credibility in my book. I would be a hypocrite if I criticized the fan for defending his 'turf'. I would do the same damn thing if a professional athlete of a rival team came charging at me in my own stadium.