Given that the technology now exists so that even local promoters can accurately place the top ten in a race - and I think we can all agree that the top ten is important - and that said technology ALSO allows the rest of the field to be accurately placed as well, why not?
There are a couple of assumptions here, one of which is reasonable and can be strongly defended, and one of which isn't.
The first, stronger one: that sprinting for places deep in the field is dangerous. I think there's a case here, but honestly I think it's so hopelessly dependent on the situation that making a generalization is foolish. The culprit for Cat 4s crashing at the end of bike races is that Cat 4s aren't great pack riders at any point in a race. Sprinting for 1st can be dangerous in a Cat 4 race, or any race, for that matter. Yeah, yeah, at least there's something at stake if you're in the placings. Right. A high placement in a Cat 4 race. If we're going to say that sprinting for 40th is important, where do we draw the line? Why is winning any local bike race worth the risk we assume? I'm with Fudgy on this one, judging guys who want to put in a strong finish is petty and low, and plenty of these deep-placement sprints are safe as can be.
Assumption two, the pitifully weak one: if we don't place riders past the money spots or the top ten, riders won't sprint for the deep placings. Can you guess what I think about this? Let me just make it 100% clear and say that I think perhaps 1% of the guys who sprint for 47th will be deterred by not getting a placement.
I think getting placements for every rider is nice. With more experience there is the eventual realization that, past a certain point, your placing is basically irrelevant. But early on, it really can be a way to mark progress or set goals. And even when you do have the experience to know it's meaningless, maybe you're in a small dropped group with a buddy and you sprint it out, and then having a placing means you can razz him about getting beaten back into 66th place by your killer sprint. Not to mention that a recorded result is a nice record to be able to come back to and remember a race. Given that we have the technology to place everyone, I only see it adding to the experience, not detracting. I see this grumbling about placing past the money as nothing so much as "back in my day" humbuggery. Technology changes the way we participate in the sport. Deal with it.