I regularly ask the waiter how large is the plate or if they do half-plate (quite common) if I'm not feeling very hungry.

If they don't do half-plate and the plates are large I might ask around the table if someone wants to split or take a portion of mine.

What's your point? That there might sometimes be leftovers even if you plan to finish it? So what? People also take left overs home and sometimes never eat them. It could very well be the case that places that don't send home boxed leftovers result in less overall waste than places that do. Especially when you consider the boxes sent home as well.

No system is perfect and a culture of taking home leftovers does not necessarily reduce waste overall.

> No system is perfect and a culture of taking home leftovers does not necessarily reduce waste overall.

Well not being able to take home leftovers does increase waste, because as others have pointed out there will always be cases where you will have leftovers, no matter how careful you are.

I’ll explain why this is not necessarily true. If you are able to take home leftovers, there is less incentive not to end up with leftovers. Hence the amount of leftovers should _increase_ as a whole. Some of those leftovers will be left in the restaurant by customer choice (resulting in waste) and some will be taken home. Some of the food taken home will not be eaten which then also will become waste.

So the question as to which system results in less waste boils down to a question that must be answered experimentally.

Reducing waste on a societal level is complex. Cultural practices of restaurants boxing food to take away may result in less waste but it may also result in more waste.

> If you are able to take home leftovers, there is less incentive not to end up with leftovers

I feel that having leftovers is never desiderable, with or without the ability to take them home. In France the restaurants are obligated to allow you to take leftovers home, and in my experience this has not changed anything on the behavior of people eating in restaurants. The only thing that changes is that in the rare case in which you have leftovers, you can take them home.

> I assume people would just adapt to the culture by generally not ordering more than they will eat.

How do you adapt and order less than 1 thing?

Restaurants are sometimes OK with splitting a dish in two/half if you ask nicely. Sometimes I do this for lunch when I'm not very hungry, and can't remember a single time someone said no.

Is this a serious question? Order the smaller food items?