It pays having speed radars in France! Not for safety as has been determined by many studies, but for the cash strapped government. Last year, the combined issued fines brought in a whopping €1.398 BILLION, that's almost 1.5 Billion Euros (at today's rate, almost US$2 Billion).
€660 Million of that collected windfall goes to the local communities, in order to help them improve roads. €65 Million is used for processing the fines (administration costs), €52 Million to maintain the radars, €20 Million to fight the increasing vandalism (I wonder why?), €18 Million to purchase and install new radars, €37 Million to put in place a new electronic and automated fine system and €35 Million for some delinquents program and €16 Million to change the old license files to the new one.
That leaves €474 Million for the government, to be used as they please. It's not going to be used to increase safety the way it should (like motorcycle crash barriers, reduction in sales tax for motorcycle safety equipment, etc... the list is long). Instead, the money will be used to fill that big black hole they call the budget.