The escapees might NOT have been terrible people.
Ok in the movie they were portrayed as heroes even though they were all hardened criminals BUT I was watching a documentary on the National Geographic channel about the incident some months ago and one day after the escape shown in this movie a man was carjacked. Three (emphasis on the number THREE) men roughed him up and zoomed off in his car and this was in the hills of Marin County not that far from Alcatraz. The now elderly man was being interviewed recounting what had happened to him and he says it happened very fast and it was dark so he never got a good look at the faces but it did occur a day after the escape and it was 3 men.
He had to walk for several hours to get help as nobody had cell phones then and in the hills there was no phone booth. Being late at nite there were very few other cars and usually people do not stop for hitchhikers or lone walkers trying to wave down help. By the time he was able to report the carjacking several hours had elapsed and he never did get his car back and the carjackers were never found out.
Now it IS possible that it is a coincidence and 3 DIFFERENT men just happened to do a carjacking the next day but IF it had been those 3 escapees I am kind of heartened that they did NOT kill the guy, they did NOT take the guy hostage (kidnapping to add to the crime of carjacking and prison escape etc) and they did not hurt the guy too badly (they beat him up a little but he was not too badly hurt to walk down the mountain for help).
Killing the guy might have been the wisest thing to do since he would report the incident and if they were afraid of murder charges they could have kidnapped him to buy time but they let him go basically unharmed.
If it was the escapees to me it gave them some good Karma which may be part of why they were never caught.