Question from somebody who has never cruised.

I've got a wedding cruise in March where everybody calls in to join into the group booking. The cheapest rate for the interior stateroom is $336 (per person, double occupancy) on the main level, which includes a $25 onboard credit but not taxes, fees, or tips. I put down a refundable deposit.

I look online at Orbitz or Kayak, and I see the same cruise, interior stateroom for $199 (per person double occupancy), no taxes,fees, or onboard credit.

Is there something I'm missing in terms of the difference in prices or amenities? How do group bookings on cruises work? Is it likely to go up if I wait?(Orbitz says the price is good until 2 days from now) Is the main level exclusive and more expensive? Would they give Orbitz the worst rooms or something? Whenever I check wedding hotels against the same prices on the same dates, the group rates are nearly always better in my experience.

I was just really surprised at the difference in prices for the same cruise, and I'm wondering if I'm missing something. Or do the cruise lines charge people more who don't shop around, even for group bookings? I'm a very experienced traveler, but never took a cruise before.