Can't be too surprised, the level of price competiton on short channel crossings must have meant that some ferry companies were operating at a loss. Seem to recall paying around £150 for car and caravan for Dover/Calais or Folkeston/Boulougne when we first starting going to France back in the mid 80s, but for the past 2 or 3 years we've been paying around £60-70 to DFDS/Norfolkline.
But I guess less competition means prices might start moving back up.