Hi guys, can you help me understand the underlined part of the following dialogue:

"What's gotten into you, Jimmy Olsen? The town's hopping with the senator's visit and you're on the first train to dream land. I didn't take a job slinging coffee for just anyone. I picked the best, I tell you, the best."

Okay, maybe this will help you. The dialogue is from Smallville: Noir. Now in these lines is talking Chloe Sullivan to Jimmy Olsen. And Chloe is the paper's editor and Jimmy is her employee.
Hi guys,

'Slinging coffee' seems like an old-fashioned expression to me, (rather like 'slinging hash' meaning food).. Where you live, do people still talk like this?

Slinging coffe means to serve someone. Chloe is saying that she feels she has helped Jimmy--now he should be indebted to her and do his job.
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Chloe's expecting him to prove she made the right decision when she trusted him to do his very best..

Did I get it right?! : p
 Clive's reply was promoted to an answer.
It is definitely slang, but women here may use it to remind us of how they were once viewed in the workplace. A secretary (in the past) was always expected to fetch the coffee; when women began to have jobs with greater responsibility they were often still expected to automatically serve the men! Anyone, man or woman, may now choose to be kind and serve coffee, but usually this is a free choice.
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