The sentence seemed self explanatory. It is obviously figure of speech.

No one is going to work for free.

SC is taking a tiny fraction of pool each day.

Weekly reward after conversion to USD is currently low, due to low price of Steem.

If it is further reduced by flags on SC posts, it will go even lower giving reward to workers that is not worth the work. No one is going to work so much for so little reward unless their lifestyle circumstances make them desperate.