I'm foolish for saving $500 every year? My old Hemi, no MDS, no eTorque got 12 MPG on my daily stop-and-go commute - my current truck gets almost 18 MPG with the same driving style. Even if gas stays at $2 a gallon, that's roughly $510 every year. If gas goes back up to $3.50/gallon, I'm saving $1650 every year. The best part? I need a truck for hauling, so I would have one regardless, but my choice of truck is saving me money year after year.
Your truck has a feature that saves you money, and you're paying more every year by actively turning it off.. kinda like leaving the back door open because you like the feel of warm air coming out of the furnace. Some might say it's foolish to pay more for a truck with features that make it more efficient, and then actively disable them. Instead you could have bought an old, cheap, dumb truck that never had them in the first place...