I'm a vegetarian for reasons of morality, rather than health or the environment; taste seems a poor reason to kill. But there are other reasons to kill living creatures, and I either guilty of or complicit in them. We all are. Any vegan/vegetarian who believes otherwise is not being honest with themselves.
It is so easy to kill. And we do it in so many ways, some direct and many more indirect.
My personal weapons of choice are my shoes and my car. I shudder to think how many little creatures I have tread upon or how many winged miracles I've turned to goo on my windscreen. And much to my sorrow, driving I have killed two birds, and possibly a cat; every day I get in my car I accept that risk as part of the cost of my transportation. And I've also killed insects I couldn't easily or safely escort outside, by hand and chemical attack.
But there are also less direct means of murder.
One of the worst ways is that I buy meat products for my dog. My dog is a rescue, so I didn't create her, or her need to eat, but out of concern for her health (which is already poor) I choose to feed her the meat diet her biology expects. My money pays for her food which pays the farmers and fishermen to do their dirty deeds. I've also supported various dog charities and their saving of dogs which will over the course of their years eat many an animal.
But even my own food is indirectly complicit. When I purchase a vegetable from the store I accept that the farmer in his planting and harvesting killed many a pest in order to get this to me; insects and animals are killed by pesticides, by traps, by farm machinery, by the vehicles delivering the produce, etc.
Of course there are also plenty of other often discussed sources of animal suffering and death I am indirectly responsible for, such as the research done for medications and surgery procedures I have been or will be prescribed, as well as products I have or will buy that I may not realize involved animal testing.
But to my mind, my greatest contribution to the suffering and slaughter of animals comes from the most indirect and least avoidable source, my every daily dollar spent. I buy the goods that meat eaters make, I pay for the services meat eaters render. My rent goes to meat eaters, my health insurance payment goes to meat eaters, my car payment goes to meat eaters, my tax supports the infrastructure of a meat eating nation, and I've employed and will employ meat eaters. And with every dollar that ends up in the pockets of a meat eater, some meat/fish/fowl is purchased, and I increase the likelihood that they will create and raise meat eating families, and that they will buy those children meat, and that...
Anyone who sees their vegetarianism or veganism as the absolute end of their complicity in the slaughter and suffering of animals is a fool. But it's ok. It's a start, and a very good start. And it's likely the only way change will come. Vegetarians/vegans would win no converts to their way of thinking by isolating themselves, converts are won by being perfectly normal people who just happen not to eat animals.
My vegetarianism is my attempt to do the best I can to create a future I want, while living in a reasonable present where I feel ok with my actions; and I think it's important not to fool myself into thinking my life or actions are any purer than they are.