Riding on the snow mobiles wasn't like anything that Skye had ever experienced before. It was annoyingly loud, but the ride was relatively smooth until they came to a hillside. The valley leading through the middle of the mountains took them about halfway to their destination.
Skye, Tidas, Klaus, Kari, Ronnie, and Arthur were all on snow mobiles by twos. Mickey and Arthur were not happy to have to ride together, but it was what it was. Ronnie and Murdoc opted to ride together because they had struck up a conversation, leaving Arthur and Mickey to deal.
The Highlanders only had so many snow mobiles that they could risk, so they were didn't have another option. Even if the creature was sleeping, there was still the risk of the snow mobiles being destroyed by the unfamiliar riders.
Crashing into trees, falling through a snow-covered ravine, or just driving one off of a cliff. The number of ways that the RMC members could destroy their vehicles were too many.