No taxes on junk food but please, in the name of God, if you weigh 400lbs don't be bitching about having to pay for 2 tickets on an airline (or train, etc.). If you use 2 seats, pay for 2 seats. Quit going on TV and crying about it.

If I go to the store and pick up 2 loaves of bread, I'll pay for 2 loaves of bread.

If you take twice as much and you have to pay for it, it's not discrimination. It's fair and reasonable.