My understanding was always that when sign posts a reduced speed limit during specific times, the speed limit during those times is reduced.
I’ve never heard of only going slower if there are kids present. You don’t always see the kids, so that is why you slow down pro-actively.
Regardless, I agree a lot of the enforcement the city does is to generate revenue.
However, if they stop doing this, the alternative is to cut police services or increase taxes. If there is less money going in, something has to give.
I have gotten the odd ticket in my years of driving (speeding, red light, school zone), but it is rare for me.
Yes it is frustrating when it happens, but at least I have some degree of control on whether or not I have to pay those (I can be diligent in following the traffic laws), as opposed to raising taxes.
Call it a stupid tax, because I feel very stupid when I do get a ticket, as it is completely avoidable.