Many people do not like the fact that animals are killed for man's food and that is very understandable. It's a principled point of view and is to be respected. Some don't eat meat for this very reason.

Many societies have moved to "choice cuts" of meat and have moved away from the secondary parts of the animal including the offal, intestines, feet and head. Other societies really relish and enjoy these other parts and have developed recipes to optimise the enjoyment. Currently there is a renewed wave of interest in these meat parts and they are being discovered by many more each day. Chef's and restaurants promote their dishes created with these and the retail prices are edging up slowly.

I enjoy most offal and in fact the only offal I don't enjoy is lung. I really don't like the flavour and have no issue with the texture. Many enjoy lung very much so this is simply a personal foible of mine. Today I was watching a television program which like many cooking shows was demonstrating a dish preparation. This dish contained various offal and I became interested. The dish looked delectable and I immediately noted down the outline of the recipe to enjoy at another time when I remember to buy this meat.
After the demo the chef gave his point of view which I don't completely agree with. His argument is that we should show respect of the whole slaughtered beast rather than dismissing less popular cuts leading to waste. The very fact is that there is no waste whether we eat it or not. The slaughter industry does not waste their assets and if the meat is not used for human consumption then the remaining elements are sold to other processors such as the animal food industry, tanners for hide product and the highly processed product industry such as the gelatin makers and subsequently cosmetic, film, adhesives and food additives. Nothing is wasted and it certainly is no disrespect to the animals.

Waste of food is an interesting topic. Those born after the Second World War will remember our mothers and grandmothers stating fairly clearly that we must not waste food meaning that we should eat everything on our plate. Those were moderately austere times but for consumer societies there is no shortage of food produced. We can decide not to eat all that we have prepared and we shouldn't feel as if the food is wasted as this non-consumed food still serves a valid and humane purpose that being food for our pets and other animals in and around our communities. They also need food to survive and feel contented and it is an easy distribution within our communities. The idea of bio-digestion of non-consumed foods is not wasteful. Sure there is a decreasing energy return on recycling but the over-all effect is not more than the production of bio-degraded material used by industry or in fact in nature. It is recycled and it does nutrify the biosphere with useable material for another crop for our sustenance.