This is one of the most shallow reasons for why Kara and Lena are a great match (especially because there are so many great non shallow reasons) but I love that Kara won’t have to worry about spending any extra money she has on food because Lena’s a damn billionaire. I know it’s a running gag about how much Kara loves food but she honestly needs a lot of it.
Kara probably has a semi decent income from CatCo but with all her expenses and the fact that she most likely isn’t paid by the DEO, every leftover penny goes to making sure she gets enough calories, especially after she becomes Supergirl and starts using her powers on a daily basis. That’s a ton of food she has to buy in order to balance out how many calories she burns.
But she never wants Lena to think she’s using the woman for her money. Never. So she insists on splitting the bill or ordering much less than she needs if Lena insists on paying and Lena finds it so damn frustrating because why won’t her best friend let her pay for her food???
Until one day it just clicks for Lena after she’s told the Supergirl secret and has done the calorie math in her head and God Kara how are you able to afford all the food that you need? and the next day when Kara walks into her apartment, she sees that Lena has finally used the key she was given to completely overstock Kara’s kitchen with all sorts meals, snacks, protein bars, etc., with a simple note on the counter saying Let me know when you’re running low and it’s stupid but Kara finds herself getting emotional at Lena’s complete acceptance of who she is.