Sure you can eat the beans and grains instead. You can also stop driving, stop heating and cooling your house, stop buying computers and phones and cars, stop air travel, live in a small apartment you share with several other people.
I don't have a problem with the idea of reducing environmental footprint or moving consumption patterns to more efficient products. Great ideas. What I have a problem with is making choices for or passing moral judgement on other people.
Your lifestyle results in the death of life and animals, and you do not do everything physically possible to minimize that, therefore you simply do not have that moral high ground. If killing animals is "wrong", then we are all wrong. "Oh but I try to minimize" is not an defense because you are minimizing according to what is convenient or valuable to you. You'll accept some killing of animals because you fly to Europe once a year or have a smartphone or heat your house and that's okay, but somebody who chooses to eat more meat than you would prefer?