The short answer is, we can’t feed everyone if everyone insists on eating meat. It’s also bad for the environment because the amazon rainforest is disappearing for cow ranches. There’s a scheme here in Belgium where no one eats meat on a Thursday and things like that help to cut down the consumption of meat to relieve some of the stress of the planet, but it’s not enough really. I’m a vegetarian and I think I always will be.
By growing meat in labs, they can grow beef in the lab. At the moment its not very cost effective you need a lot of cells for a tiny bit of meat but it has been done and was edible. maybe in the future we will be eating lab grown meat!
If we all insist on eating meat and there isn’t enough for all of us, meat price is going to shoot up like crazy until the demand for meat is balanced by the supply of it. It’s all about economics in this case. Now, if it goes too high, there will be a market for new technologies to produce meat more efficiently… that means we will have more scientists funded to research ways to produce bigger cows, bigger chickens, and bigger pigs! Do we really want that? Some think we don’t… so a number of people prefer to turn vegetarian and limit their consumption of meat products.