There is a real taboo around death in many modern countries and perhaps that isn't healthy either.
I saw an exhibition of Maggie Hambling's art at the British Museum the year before last. She had drawn her dead mother. I think perhaps to an artist their art is the way in which they connect with the world and make sense of it. I don't see that as disrespectful. Perhaps it is the same for other people.
I wouldn't want to take photographs of dead loved ones but I wouldn't criticise those who do - everyone has a different way of responding to death and of paying their respects to their loved ones.
I have taken photographs of funeral flowers, the people at a funeral and the messages that they leave. I wouldn't share them with the world because that is not my customary behaviour. Again, if other people want to do it, I can't really see the harm but I don't really understand why people other than those close to the dead person would want to see such images.
What I do think is thoughtless, and possibly disrespectful, is people looking at their mobile phones during celebratory and commemorative events. It implies a lack of interest, emotional connection and attention - and a strange understanding of what is important and what is not.