When I grew up in India, we didn't have "supermarkets" to process food, we would go to a market which had butchers, fishmongers etc. The butchers usually had live chickens that they would slaughter right in front of you. I believe they use the halal method where they slit the throat of the chicken and then put it in a box. The chicken knows whats happening when its fetched from the overcrowded cage, so it cries a very loud, pitiful scream.... that caused me much alarm as a little kid to hear it scream in pain :( :( :(.