Here in Canada, DRLs are mandatory and frankly I don't find that annoying. Heck, I find it weird when I see an older car without DRL and amidst all those with the lights, I spot the older car a little later than usual. And if you think people are stupid cause DRLs don't turn on the taillights, when it was raining lightly this past week, most of the cars had their headlights on anyway.
Actually, come to think of it, I don't think DRLs might be the problem to people forgetting to turn on the lights at night (since you'd figured you'll know when the lights look dim) but it's because of the electroluminescent gauges that are being incorporated into more and more vehicles. Those that come with that and are missing the auto-headlight feature (e.g. Corolla, Civic, Acura EL, Mazda3) have a higher rate of forgetfulness on the driver's part. These gauges are lit brightly all the time and if it's dimmed down during the day, it'll be at a tolerable intensity at night and hence people might think their headlights are on since the instrument panel lights are on.