There are at least two reasons for not buying the huge, military-type vehicle called a Hummer. then of all, Hummer’s big gas hogs. Second, when gas costs $3 per gallon, it costs $100 to fill up a Hummer's big gas tank. Next, Hummers are bad for the environment. Also, the H2 model gets less than 10 miles per gallon of gas .After that in one year, a Hummer gives off 24,100 pounds of carbon dioxide, which is two to three times more than average cars give off. To sum up, for the health of year bank balance as well as for the health of the environment, don't buy a Hummer.