Season 3 episode Con Artists

Yes, home repair / improvements scams still exist. 'Travellers' (of Irish origin), among other (sometimes ethnic) groups, offer to fix the roof or pave the driveway in suburban or rural areas. They don't finish the job, use substandard materials, or burgle the house while the homeowner is preoccupied, etc.

I don't think the studio wanted to offend any particular group (like Romanian gypsies) and get bad press - like 'The Untouchables' TV series when Italian-Americans complained about all the mafioso bad guys - so they made the 'villains' white-trash stereotypes.

Yes, as Badge noted, those scam artists are still around, unfortunately. Altho I'm not sure how often they're large families doing the scamming. If you're in the NYC area, I'm sure there were lots of scammers on the prowl up that way after Hurricane Sandy a few years ago. They always seem to show up after severe weather hits, ready to offer their 'services' to storm-shocked homeowners. Often it's roofing, but it can also be tree-limb removal, driveway repair, etc. Handy rule of thumb for homeowners is, don't hire people who come to you; much better to get estimates, check word-of-mouth, and then call them. Sadly, people do still fall for these creeps.