How to hack the freeconomy

I have come to realise, however, that I am nothing but a novice. One popular route to free riches involves a "referral code", which gives each person who uses it a credit for helping secure new customers. Felix, who runs a startup in San Francisco, has taken this to extremes. He accomplished what he calls his "Bay Area hack" by buying around $600 in advertisements on Google and placing his referral code from Uber in each ad. He spent hours fine-tuning his approach until his ads often had a higher click-through rate than Uber's own. For each person who signed up to Uber's service through his ad, he received a credit. He eventually amassed $30,000 in credits, which allowed him to ride around the city in Uber's cars and eat three meals a day from UberEats, the company's food-delivery service, for a whole year without paying a cent.

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