Another alternative if you don't want to leave early is to draft one another as in a pace line formation. But that technique is unfortunately fraught with problems since you undoubtedly have some riders that are slower and can't hang on the back and those who won't take a reasonable pull at the front. This is a great technique but you have to have the right talents and personalities involved. Oh and think about buying the lead guy's lunch if he has buried himself most of the morning for the group, or at least acknowledging their efforts verbally will go a long way.