Or stated another way: even the most expensive headlamps you can install on an A-body are orders of magnitude cheaper than a crash. Body parts for cars are expensive; body parts for people even more so.
And a couple feet of visibility is a pretty small difference. Brakes are the same way, the improvement in braking distance keeps getting smaller and smaller as you continue to upgrade further. But a couple of feet can be the difference between no damage at all and thousands of dollars in repairs or worse.
Obviously there's more expensive/better stuff out there than what I've got on my car, I don't have unlimited funds to chase diminishing returns. But I will certainly do my best to upgrade safety equipment like lighting, braking, handling performance etc so I can keep driving my car the way I want to.