Chanta is slang from
ciantapuf, a person who deceives, a cheat, in Italian slang. In Argentina, the spelling is phonetic and only the plural form is used. It became
chantapufi and has a similar meaning.
Ese tipo es un chanta, no le des bola. (That guy is not trustworthy, don't follow his advice or That guy doesn't know what he's talking about, don't listen to him.)
But, often times, friends call each other
chanta. It's one of those words whose meaning changes a lot depending on context. For example, a brother may tell his sibling, Dale, che, no seas chanta que me prometiste que me ibas a prestar la campera. (C'mon, dude, don't be
flaky, you promised you'd lend me your jacket.)
@Calgary Foodie, I asked our server about the name, he said that some years ago, at another location, a customer got mad at the owner and left the place shouting "gordo chanta!", as an insult. The owner laughed and replied,
Thank you for giving me the name of my next pizzería.