No, god no, in Australia we've seen an increase in utility prices (could be the Carbon Tax that we had voted NOT TO HAVE!!!!, electricity is majorly caused by "gold plating" the maintenance and upgrade of the power-lines) and the major banks lying out of their asses saying they're struggling (hundreds of millions in profit is not struggling) so they try and keep interest rates as high as they can. these factors push up household bills and because of it, some families have to go without certain things like air-conditioning/heating, night outs ect. these people turn to fast/junk food because it's cheep and keeps one from starving, putting a tax on it will increase the prices and make things harder on them
plus alot of people who are seen as "obese" are actually healthy and their being judged on their appearance, i'm a bit big around the belly myself and yet i'm able to help load/unlock 16 bales of hay that feel like they've got bricks in them, i help move showers and kitchen setups between 2 houses and one of the kitchen setups i helped move had a granite top which makes it bloody heavy, i'm not unhealthy, yet people would see me as that just because of my belly size
i also have the suspicion that that Gilard Government, knowing full well that all the prices cuts they have made to hospitals, education, family payments isn't going to get them the budget surplus by 2013 (the last promise they've made during the last election that hasn't been broken yet) wants this tax so they can get more money cause they know that Gilard will not retake office if they don't get this surplus as people will see Gilard (and labor) as useless (the only thing she really has going for her is that she's got people fooled thinking she's got it rough because she's a woman, she's got it rough cause she's prime-minister and she's doing a horrible job which makes comedians pick on her even more, had she been a man and she would get the same treatment)