Carp are a great sport to catch - and can be huge. I caught many a carp as a kid. But after decades of watching what these bottom feeding muck rakers do to spawning habitat I detest them and would be content to see them all but extinct. I live on a small lake and watch these muck rakers every year disturb spawning areas. Very similar to what Gar do.

Having said all that,the Grass Carp has been introduced in some ponds to clean up the grass problem. They are virtual eating machines. Fisherman are warned not to keep/kill these fish. I understand they are very expensive to buy and stock.