“The risk also is that if you get cancer you never know why. 30% of cancers are down to lifestyle, 60% we don’t know 10% genetic. So an overweight person will automatically think it was their weight when it could have been other factors. It’s lazy advertising in my opinion.”
No it isn’t. Anything that increases the risk of cancer should be made well known IMO. Even reducing the 30% is better than nothing 
“I hate what they're doing because it smacks of victim blaming and suggesting that getting cancer is your own fault.”
No it doesn’t. I think we spend far too much time tiptoeing around people these days for fear of “victim blaming”, which IMO is an over-used expression. Sometimes you just have to spell out the risks to people who are in denial about their lifestyle and the risks it poses to their health.
I don’t get why so many people don’t understand the statistics of risk factors. Any intelligent person will know that you can get cancer/have a heart attack or stroke/develop diabetes through no fault of your own or genetic predisposition, BUT will at the same time understand that some lifestyle factors do significantly increase the risks. It isn’t rocket science. These statistics have been scientifically researched and are proper scientific data as opposed to anecdotal “data”.
There was a publicity campaign earlier this year about obesity increasing the risk of cancer. Clearly it wasn’t very successful judging from some of the responses on this thread.