Thanks for all the responses everyone. Some very good questions and suggestions.
I did a bit of asking around and, unfortunately, it looks like the reason for the day trips may be the weather. Specifically he does not like camping in the rain. There is rain in the forecast for our Klondike this weekend (raining now actually) so that fits. best I can remember there was in rain during previous outing weekends. Again, this isn't the official answer from leadership (no real answer is given when they are asked) but it fits.
I can say with confidence that the problem does not lie in the organization. We are fortunate to have some very active adult volunteers in the troop. The activity calender is planned out a year in advance. Transportation, the the best of my knowledge, has never been a major problem. If they ever need some extra seats they send out an email and parents answer the call. The grubmasters and quartermasters do a very good job with their equipment and purchasing.
Under the previous scoutmaster, the troop would go camping no matter the weather. In fact, I remember one of the scoutmasters making the remark 'you can't learn how to camp in the rain without camping in the rain' when heading out on a trip during a downpour.
Now I just need to figure out a way to discuss this issues without causing any major problems. While asking around I discovered I'm not the only one with this concern. The boys missed out on a large part of our council's Wizard Safari (http://www.wizardsafari.com/) and looks like their going to miss out on a lot of the Klondike adventure all because of rain.
Of course this also means I need to put my money where my mouth is. If I expect someone to take these boys camping in the rain, I better get trained so I can be one of those someones.