There is just so much nuance to this problem that there really is no easy answer. We live in such an intertwined society that all of our actions have consequences for others. Obesity drives up healthcare costs for all but at the same time, the majority of obese people here in the US live below the poverty line. It is becoming a problem for everyone. Like I said though, there is a lot more going on here than just "get unfat!" Fat shaming does tend to work in certain environments where health and appearance are steeped in local culture but it certainly would not be effective here in the western world. Especially given the fact that obesity here in the US can often be attributed to, or a symptom of, another mental or physiological condition such as depression or organ failure. One thing I think would help is if we were to put more restrictions on EBT as to what kinds of food products can be purchased with the funds. Subsidize more fruits and vegetables while removing subsidies for corn and meat products. Corn being so cheap and heavily subsidized has made meat much cheaper, and much cheaper meat has led to unhealthy proportions at meal times. Not only will it drive up the prices of meat, but unhealthy corn based snack foods as well. People need to learn moderation. There is certainly a lot that can be done but then again there's the argument of government interference with individual freedoms.
