And if 0 drivers are fined as happened here, what then?
You imply then that a DUI checkpoint is some sort of money making scheme and that the end point is revenue. No, the end point is to arrest drunk drivers, who do in fact kill people. One could argue that if no arrests were made, then the campaign was successful.
However, I do find it rather odd that 1200 vehicles were stopped and no arrests were made. The odds of 1200 people not having an outstanding warrant among them, or other issues is very strange.
I the end, these checkpoints are fostered by groups such as MADD and are meant to deter, rather than make a lot of arrests.