I think this varies from place to place, from country to country.
We wouldn't say "huckster" in Canada unless we meant a dishonest person with inferior merchandise, selling aggressively.
I think we'd just say "people who sell things on the street."
We do say "vendor" sometimes. It would be normal to call someone who sells hotdogs on the street a "hotdog vendor."
Selling things on the street isn't as common in North America. I don't think there's any specific word for it. "Street salesmen" sounds okay and would be understood.
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