I have alsways suspected that if people in the US had to slaughter and butcher their own meat they would eat far less of it. We are so removed from the process where it is already portioned, chilled and wrapped in plastic, that we don't even associate it with the animal. I have had to butcher a large animal (deer) and it is not fun work. The smell when you open the body cavity.... Do humans smell like that when they are opened for surgery?
Humans actually don't smell too bad until tissues are rotten from gangrene when the smell is as bad, or worse than a rotting corpse. But the smell of flesh being burned by cautery smells just like meat cooking.
Your point about why people might not eat meat if they had to do their own slaughtering is a valid one and there is a lot more to this story.
I believe that Western nations long long ago decided to adopt "humane" methods of slaughter in which the cattle are first knocked out with an electrical charge to thehead and the culling is done on an unconscious animal.
As far as India is concerned - India in 2007 produces more milk (and methane from cow-fart) than any other country in the world and probably has more head of cattle than any other country.
But in the era when a ban on cow slaughter became a popular idea several social factors were at play. The cow is considered sacred, and that sanctity has come from several factors. I suspect that the usefulness of cattle entered into Hindu folklore and made them sacred.
Cows of course were "wealth" and a family with cows had a steady source of income, dairy products and fuel (dried cowdung). I don't think cow eating has been big in India for centuries - I don't know if there are any written records on the issue.
However (and I am guessing here) "cow eating" re entered Indian life with a bang with the first Islamic invasions. That played havoc with the life of many people in India and Muslims in general are unlikely to be forgiven anytime soon unless there is an active reconciliation or past with present.
The "ban on cow slaughter" is a great political riposte to the forces that were seen as having upset the peace in India in the first place. The "rationale" for initially opposing cow slaughter was that at the time of famine it was important to preserve cows for a vegetarian population and not slaughter them. That rationale no longer holds true.
I believe beef/cow slaughter is very definitely a quid pro for what is perceived as a persistent trampling of Hindu rights by savages.
It can be sorted out and it will be sorted out after there is more widespread acceptance and acknowledgement that Hindus had a particular way of life that was seriously damaged.
The treatment of Hindus in india is seen by Hindus as somewhat similar to apartheid, except that there is no acknowledgement from the alien forces that entered (Islam and the Church) that such discrimination existed.
As long as that occurs - there will be this sort of battle going on in India, a reflection of which is seen in these threads.