Coercing / encouraging over-consumption from your consumers is a proven profit-driving strategy.
Yes, as Possum577 just pointed out, there is a culture of over consumption which enables this to occur. If there wasn't, it wouldn't be a profit-driving strategy because everyone would say "Sorry, I really don't want this much food, I'm going to shop elsewhere which provides more reasonable portions." Which would then force businesses to change to accommodate this, lest they be out-competed.
Portions at US restaurants are bloated to three times the necessary amount of food so that they can justify charging you twice what it really costs to fill your belly.
Again, as a consequence of the prevalent over-consumption culture. If there's any merit to what you've said here, the logic reasonably follows that businesses would bloat portions to four, five, why not ten times, the necessary amount of food, to get an even greater return in profit at the expense of what the consumer actually needs. Why not make every individual consume 10k calories in a single meal? Fuck it, they don't have any control over their decisions whatsoever, right? Squeeze every last penny out of them, that's the "capitalist" way!
But of course that's facetious because people do have control and they do decide how big their meals will be by consenting to the decisions of businesses, selecting them over businesses with alternate portion sizes, or over just making their own meals to their choosing. Your assertions really just boil down to taking the people who cause themselves problems and telling them it's not their fault, providing a scapegoat "the businesses" and "capitalism" as the proposed core of the issue. This is no good for the people who continue to kill themselves through overconsumption because it makes them wait on someone to come save them from whatever scapegoat you've provided, which is of course the far easier thing to do, where instead they should begin realizing they're at fault for their actions and should hone up to them i.e. be responsible, the far more difficult and, of course, less popular route.
Even with all that said, the individual could easily save their meal for later, nothing forces them to consume the entire meal in one sitting. You're
tilting at windmills, classic mistake.