I thought the first helper in Peru was suspicious, but not the rest. Romber is famous around the world, as Survivor airs all over. Plus, their photos were plastered all over magazines and newspapers too. They look great and also have that romance thing going for them, which gave them even more press and additional fans.
On Survivor All-Stars, Rob exhibited an uncanny knack for getting people aligned with him even if they hated or distrusted him. His background in the construction biz also gave him experience organizing crews and getting people to work for him. It's a charisma thing. Some guys are just natural bosses and if they are also pleasant and funny, as Rob is, people practically line up to work for them. Racers in subsequent Amazing Race shows may learn from watching "the Robfather."
I find him fascinating to watch. Amber too. They are a well-matched pair, a press agent's dream, and their audience-appeal has raised the ratings of Amazing Race, a good thing for those of us who want the show to go on and on and on.
If you read Rob's bio, you'll see that he has a Bachelor degree in psychology. Interesting...