Do not be so quick to judge the people riding in those carts. It may be that the ones who are overwieght are riding for a different reason.
My wife--like I am--is overweight, but that is not the reason that she has ridden in the electric carts, at the City and Walmart, too. She has ridden because of her artificial hip--she is on the third revision of it--the result of a Giant Cell bone tumor that ate her pelvis and femural head when she was 28 years old. Now at 44, it looks like loosening of the hardware is pointing her at yet another revision. That means she'll have to ride the carts again for a while.
The last time, she got some dirty looks and snide, under-the-breath remarks about riding them just because she was fat. 'Fraid not, folks.
Next time you see someone on those carts, think twice before assuming WHY they are using the carts. "There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy." And: "As ye have done it unto the least of these, so ye have done it unto me."