I pay extra so I don't have to do that. Carrying a waterbottle and a lunchbox was a significant contributor to my negative mental health as a teenager, and my life is way more pleasant without them.

In a similar vein, eating food that I don't want to eat is very stressful for me, and I generally can't know what I want to eat more than a couple of hours in advance. So eating food I prepared myself is usually rather disappointing.

Third, food waste. I never eat the same meal more than once a week if I can help it. That means that, when I buy a tomato, I end up only using a single slice and letting the rest rot in the fridge because there really aren't all that many things I like that have tomatoes. The same goes for most ingredients. If I don't use it within 4 hours, I may as well toss it, cause im never going to eat it.

I've tested out various ways of eating, and eating out often is cheaper compared to constantly re-buying ingredients for meals I'm not going to eat.