There are 8 teams in the Pacific Division, 6 of them play 68 games and 2 of them (Texas Stars & San Antonio Rampage) play 76 like the rest of the league.
The 6 teams that play less are all located in California (except for Tucson, which is in Arizona). The other teams that play 68 games are the Ontario Reign (Kings), San Jose Barracuda (Sharks), San Diego Gulls (Ducks), Stockton Heat (Flames), and Bakersfield Condors (Oilers).
This is the reason why the standings are always determined by winning percentage instead of points. This is also why the Rampage are last in their division, even though they are 3rd when you only count points. But because they played 8 more games than most teams in their division, their winning percentage is the lowest in the standings.
It all started a few years ago when the NHL teams decided to bring their AHL affiliates closer. What they asked, with the backing of the NHL, was to have their farm teams to play less, travel less, rest more, and practice more. The AHL would either agree to that condition or the NHL was prepared to start another development league to accommodate the parent teams. The AHL agreed to those terms and for the last two seasons, 6 of the 30 (soon to be 31) teams play 68 games instead of 76.