For us it's a tradeoff for:
1. Convenience vs inconvenience
2. Additional fuel
3. Unexpected maintenance to the toad
4. Potential damage from the Alaskan Highway
For 2013 we averaged $4.35/gal 9,600 miles round trip from Phoenix for diesel and diesel was $0.20/gallon LESS than gasoline in Canada. Expect to pay $5-6/gal in N Canada. We didn't initially protect the toad and now have rock damage to the paint and replaced the windshield when we returned.
Using a 26' MH for local transportation is doable however, IMHO. We took a 22' MH from California to Newfoundland and back with 2 teenagers and no toad.