@ Charlie, I'm grateful that you, "don't have a problem with" our choosing a vegan lifestyle. Thank you. Yesterday, a guy told me he had no problem with my not owning slaves. Unfortunately, when I suggested that his ownership of slaves was evil, selfish, and cruel, he said that I should follow my own conscience and let him follow his.
There are other sites where we can discuss overpopulation and other environmental problems. Here we are talking about ethics and compassion for our fellow earthlings. Unfortunately we are often reduced to using examples that appeal to self interest, when those we debate display no sign of compassion to which we could appeal. To me, the ethics of our relationship with other animals has nothing to do with "resource management". Other animals are my friends and relatives. They are not my possessions, nor are they natural resources for me to manage.
Johnny, you admit that you have not researched thoroughly, or at all, the topic of protein for vegans. Please do so. There are hundreds of articles readily available through any search engine. Lots of books in the stores and libraries, too. But just think, what is the biggest strongest, most muscular animal you can think of? What is his diet. What do the bull, the elephant, and the gorilla eat? Google vegan athletes. Tony Gonzalez is only one of many famous athletes who are vegan.
How about Carl Lewis. There are many others.