Without all the facts to hand it's hard to comment on. Thoughts are with the spectator over football any day.
Who's not to say that the weight of the chopper landing on the pitch didn't cause damage to the playing surface, hence the Ref having to call it off?
Chopper could have been anywhere before finally landing at Barnsley. Again you're talking time for the medical team to get to the patient, assess, deliberate best course of options and the time to finally get the patient in the chopper and away from the area. Many reasons for the lengthy delay and all will be explained as to why what took place had to happen.
Not a million miles for the Burton fans to travel who I suppose will in turn and accept, like the Barnsley fans, what were an unusual set of circumstances.