Those prices probably give an indication that on those two days the boat is fairly full. It may come as a surprise to you but the airfaires are fairly high around those dates as well
I'm going across on the 24th to the 29th of December, I'd much prefer to take a car but the SP want £300. Manx2 want £160. So I'm flying. A real nuisance not having a car, but I can't bring myself to pay the extra £140.
The SP have got to be losing customers with their pricing policies.
How much are the Taxis charging on the 24th on the IOM,UK Train Prices are also high on these dates, maybe its a Holiday period. Do you not think that the SP may have extra costs over the Xmas, what happens to the crews, do they stay on the boat Xmas day for fuck all.