The wolf of wall street types, if they are good at cold calling, they nowadays cold call for offers of their own or offers in which they are directly affiliate marketers. Nowadays, with the available technologies & platforms, everyone wants to maximize the earnings from their skills and people do not want "dilute" their earnings or rather want to "diliute" their earnings to the minimum possible extent. The same goes with people who are effective in cold calling. No point hiring cold callers who would not be effective in cold calling.
The moment they learn well enough, they will tell you "bye bye" and they will replicate what you taught them, to earn directly on their own. Remember, people are business minded and money minded when it comes to earning money. The effective ones who are smart enough, will eventually do what they learn, on their own, in order to maximize their earnings.
In which country?