Having just got back from seeing the film, it's interesting how well the beginning is coded to lull the viewer into sympathising with Judy's view as the marginalized outsider.
It's more than just the greater narrative, it's unspoken details like how Bunnyburrow station has room for all the different levels of the carriage to have their own exits, but the city station only has the one 'normal' sized exit. Also, things that just aren't said, like how Chief Bogo doesn't try to justify putting Judy on parking duty, despite the fact that viewed objectively it's a pretty sensible move. It gives the new recruit a safe position to explore the city and get a sense of the streets for their first day on the job - although Bogo is obviously being more than a bit of a jerk about it.
All of which means when the viewer runs into Nick, who is so obviously coded as the Loveable Rogue type, you see him from the view of an authority figure whose internal narrative is turning sour. For a startlingly long time I found it really easy to see him as an antagonistic figure, mentally approving of Judy's 'ingenuity' in abusing her authority to keep him on her leash.
When Judy first comes across Nick, he seems like a kind of narrative payoff for her hard work - you did your time ticketing cars, here's your chance to do A Good Deed, the kind of thing you came to the city to do. So when it turns out to be a scam, it poisons an otherwise good day, casting Nick as the catalyst for the string of events and realisations that try to trample Judy's dream. So when she realises he's her lead to finding Emmett, there's a certain sense of 'at last, delicious payback' to how she treats him…
But if the film had followed Nick up until that point, you'd have a tale of a guy living hand-to-mouth through ingenuity and harmless (mostly legal, even) hustles, until a police officer yanks him out of his life (and he clearly doesn't have a stable income*, so yeah, time is money) and entraps him via her authority with a vindictively gleeful ironic echo of how he… Uh, stiffed her some pocket change.
By himself, he's a Loveable Rogue type character just trying to get by and not really harming anybody. But Judy's narrative casts him as a petty crook, which justifies (to herself) yanking him around for the sake of her dream, her job, her priorities. It's a pretty slick piece of foreshadowing and setup for Judy's eventual realisation and triumph over her own prejudices. Her biases are on display from the outset, simply allowed to slip under the radar as much as real peoples are.
* The actual economics of Nick's situation are kind of nonsense, but he's clearly a drifter with shabby clothes (that shirt looked positively grimy when I first saw it) and treated like an outcast by society. He seems slick and confident, but then, never let them see they get to you. Was he homeless before the city turned on predators? I don't know, but it seems to fit.