Some people are so oblivious to what's going on around them that they don't even see blue flashing lights on emergency vehicles. DRL's are not the problem, its peoples awareness or lack of giving a toss.
Very true. I've seen this a lot more when sat in traffic and a emergency vehicle has been coming in our direction.
One in particular was a young girl in a Fiat 500 looking down into her lap (Presumably on Facebook/Instagram/Whatsapp etc) only when the Ambulance was right behind me and her (She was in the right hand lane) did she eventually move (All in a panic I might add). I just shook my head at her when it was all over.