Hop turns have their place. If a carved or slarved turn will take up too much horizontal space (the terrain is too narrow), then hop. If a carved or slarved turn would generate too much speed, hop.
[The following discussion is presented in the context of dealing primarily with deep or heavy snow on terrain of moderate to high pitch. It can also be applied to narrow (couloirs or chutes) or restricted terrain (trees)]
Hopping can be very tiring. Too many put their effort in going up when going out is easier and more effective. By going up, you are lifting your body higher than necessary when by going out you take advantage of the pitch to gain distance between your skis and the snow AS WELL AS you get further down the slope necessitating fewer turns to cover the same amount of vertical pitch. The only need to go up is to have your skis clear the snow they are in to prevent twisting out of the bindings.
Consider, also, that the steeper the terrain, the more likely your twisting skis' tails are to hit the snow behind you. This is another reason for projecting horizontally away from the slope rather than vertically; you gain more room for your skis to swing around.
I'll agree with
@Josh Matta to say that you can use the skis to empower your hop turns by not stopping between each hop. Let the reverse camber of the ski help you pop back up and out by doing continuous turns, akin to not traversing, but linking your turns. Also, many revert to hop turns before needed. Control your speed with complete turns and let the ski develop a big bend to carve through manky snow rather than revert to hops. Most times if you control your speed, you'll find you can turn your way down treacherous terrain rather than resort to hops.
I use hop turns primarily when the path is less than a ski width for an extended distance. Otherwise I let the ski carve and fly/pop out of the snow during transition so, as
@Kneale Brownson points out, I'm making an edge change out of the snow. This can look like 'old school' powder technique, but they did it for the same reasons that you'll want to try it. To get the skis to change edge AND direction without yanking them off your feet by applying strong rotary movements while the skis are IN the snow.