I've heard this story from someone else who saw someone collapse on a jogging trail in a park. She did CPR and said she had his skin pink when the EMTs got there and just sort of dicked around as he obviously declined and died (he may have died after they picked him up, but at any rate the responders did not continue CPR like my bystander acquaintance). When I heard the story, she was still furious over their lack of urgency and how she felt like they'd thrown away a good chance at getting the guy back.  


By no means am I using that story to impugn the reputation of first responders, but I wonder how common that scenario is - that someone losing their shit is so commonplace that you don't jump to it like an unseasoned bystander might.