When Grubba told Jolene "I love my job! I'm never going to retire!", she didn't realize that it was a threat.

Grubba and Jolene from Chapter 3 of Paper Mario: The Thousand Year Door. The remake has been a blast and it really elevated Grubba in particular by giving him extra animations that made him look like an overexcited goober.

What makes Grubba such a compelling character is that he's NOT just in it for the money! He genuinely loves his job and has a fine appreciation for the sport, even if his actions go against the very nature of the sport.
He's just a Kentucky Fried Bastard.

I like to think that most of the money made by the Glitz Pit goes right back into the Glitz Pit, and the main reason Grubba even has a secretary in the first place is because he'll burn through the budget if no one is there to wrangle him in.