Certainly, pinch the growing tips out (just above a leaf axle) to make them nice and bushey. Next year when they are growing well perhaps take some cuttings yourself.

I took cuttings from a bunch of Supermarket Carnations last year, and they are looking lovely,so yes,take cuttings for next year.. Mine overwintered in a cold Conservatory,so they should survive ok..

Jimmytheone and Bloomer thank you for your helpful comments.

If the nipped out pieces are long enough then use them as cuttings.

Thanks Owdboggy.