You are absolutely right, especially if you do your homework. The Seabourn website always has various cruises at bargain rates, or with free airfare. In addition, certain times of year are usually inexpensive, e.g. the first two weeks of December, the weeks directly after New Years, etc. If you're a past guest, you get an additional 10% off the "best" fare.
The 11 night cruise we just booked on the Pride for mid-December cost us approximately $2850 per person (not including air), which averages out to $259.00 per person, per day. That price includes all wines and liquors, truly gourmet dining, outstanding service, a no-tipping policy, great destinations (St. Bart's, the French side of St. Martin, Virgin Gorda, etc.), and the most beautiful cabins I could ever imagine. In my opinion, that's a bargain.