They can be. I'm a solo travelers and have gone on 2 thru the casino and one with carnival via the casino.

As a solo traveler/cruiser it's great because you don't get hit with the dbl occ sup fee. That's great for me. so for an inside cabin from New Orleans or Miami for 7 days, it's only about $360 total. A 10 day is only $660 approx.

Depends on ones cruise preference.