These rule systems cover both the killing and preparation of all the food that you eat.
There are many benefits to kosher food. For example;
Kosher meat is healthier. USDA standards are disgustingly lenient regarding the animal's health. "Sixty Minutes" once did an expose on this--many kosher butchers reported a large increase in gentile customers. Cold-water plucking helps prevent the spread of salmonella bacteria, and meat from diseased animals cannot be considered kosher. Kosher slaughter is more humane than non-kosher slaughter, as it kills the animal in a painless fashion. Although kosher slaughter does not kill the animal instantly, the animal passes out from the sudden drop in cranial blood pressure and dies in a minute or so. There is no pain. source about.comAlso animals killed in kosher slaughter houses die in less pain and tend to be healthier then animals in normal slaughter houses. source
I believe that both of these facts are enough to win the argument that we as Pagans should be concerned about whether our food is Kosher or Halal.
At the core of both, outside of the part about God and religion, there are sound principles for both dietary restrictions and for food preparation. And with the prohibition of animals suffering in kosher slaughter houses it also falls under the Rede of 'harm none'.
So take the time to research Kosher and Halal practices and try to apply as much of them into your life as you can. Frequent your local Jewish or Muslim butcher and buy there if you can. I do not urge becoming Jewish or Muslim or even completely and utterly following the guidelines religiously. But I do urge you to be more conscious of the food you eat and how it makes its way to your table.