He was one of the biggest names during the Attitude Era so a lot of fans who watched during that time period have fond memories of him and are marking out that he's back again. He's also one of the few who is allowed to swear during RAW and I'm pretty sure he gets a lot of freedom when it comes to his promos (which is kind of unfair to the rest, yes, but he has earned it), and even though the product is PG most fans like the attitude stuff anyway. He also hasn't been exposed as much as someone like Cena who's been on our TV screen non stop since 2005 (longer than Rock's full time run) and pushed down our throats.
By the way he did get booed in 2003 remember which is why he turned heel to Hollywood Rock. Which then made fans like him again
It's The Rock. People respect him. That's the difference between Cena & Sheamus and The Rock.
Cena & Sheamus try to get respect when they are booed, they are push too fast so people just boo them and don't care if they do good things.
The Rock gain the respect of everybody before being pushed so nobody boo him because they respect everything he have done
Why would they boo him? CM Punk is no where near popular enough to have the fans boo the Rock especially as a heel. I'm sure CM Punk will get some cheers at RR, but I'd be shocked if the crowd was any less than 80% (at worst) in Rock's favor.
Top 5 NXT - Bayley's Ass, Sami Zayn, Kalisto, Kevin Owens, Tyson Kidd
Top 5 Main Roster - Brock Lesnar, Dean Ambrose, Ryback, Bray Wyatt, Randy Orton
Top 5 All Time - Rey Mysterio, The Rock, DDP, Stone Cold, Chris Jericho