I stand by what I wrote. The human mind is generally not that rational and literal, especially when scanning a long list of headlines. The brain sees "$2500", "a day", subconsciously makes a connection that $2500 is more than the reader typically makes in a day, interest is created, link is clicked. No one proceeds to conclude that man is earning $912,500/year, but the connection is made and it's quite intentional from the headline writer.
Here's another example:
"Man makes $2500 in a day by buying a lottery ticket".
That is a weird sentence, because buying a winning lottery ticket is a discrete, non-reproducible event - so why include "in a day", unless it is to suggest something to the reader?
Or another one:
"Man makes $2500 in a day by winning competition after preparing for months" - you can see where I'm going with this.