Wondering about leftover food in Islam

Salam! I had a situation recently that got me thinking about Islamic views on food. A friend from Morocco, who's studying here, couldn't come to my holiday dinner, so I packed some halal-certified leftovers for her to enjoy later. I called it a 'doggy bag,' which is common slang where I'm from, but she seemed really upset by that term and how the food was handled. Now I'm trying to figure out why-is it a cultural or religious thing about dogs and food? I know Islam teaches not to waste food and encourages sharing extras, but maybe there's a specific, respectful way to offer leftovers? If anyone has insights, I'd love to understand better to be more mindful in the future.