Why the usa dont raise and harvest kangaroo like cows? how fast do they grow and cost 2 grow compared to cows?

i read that kangaroo meat tastes like beef, is healthier and they are much less harmful on the environment. yeah you can get it imported i think but why not just raise them somewhere in i dunno texas maybe. how long have we been eating ostrich here in the usa? not as long as cows i know. maybe some people dont want to eat kangaroo jack ohh thats mean. but aside from that what reasons could be holding us back from this? i read that they kill them with a single shot to the head a ton more humane then how we kill cows.