Nick,
It is helpful to remember that the NPS was created to enable citizens to visit and enjoy what the park incorporates. That is the mandate under which they receive funding. National preserves on the other hand are in the business of preserving natural conditions to the extent possible.
It isn't a matter of being conservative -- but it is important to remember why those parks were set aside in the first place. If the NPS didn't provice amentities and services to visitors they would not be fulfilling their task.
The only branch of government that is supposed to make changes to that mandate is the US Congress. At the present time, the presidency is trying to use the national parks as a place to obtain resources (eg: fuel) -- that is probably an example of an over-step of authority AND THAT poses a far more dangerous threat to the parks than a few bathrooms or lodges.