Comfort usually comes with a penalty paid at the pump. Depending on how many bodies you have to move, big vehicles are more comfortable than smaller vehicles, and then there are a host of variables that factor in—bigger is more comfortable, plusher is more comfortable, loading up weighs down the vehicle, weighty vehicles are harder to move, more power is needed to motivate heavier vehicles, and more power saps efficiency. Follow the line of reasoning, and you see that comfortable vehicles are often less efficient.

Source: https://www.topspeed.com/suvs-that-big-comfort-without-big-fuel-bills/