If I was a dog I wouldnt eat just processed food either

Have you considered the benefits of a natural or home cooked diet?
Not only does it cost far less it is 10 x better for your boxers!
Processed foods are OK in moderation but I am a firm believer in '
We are what we eat!"
Dont imagine it will take ages to prepare either as I feed 5 boxers daily and often extras on the weekends and it takes me but a few minutes from my busy day to toss this and that into the bowls.:D
Dry foods are given at a different meal , so they do get some processed foods but merely for a nibble.
Give it a go.
It does initially take a little getting used to as you have to restructure your thinking to this way but honestly it a breeze!
I keep a constant supply of defrosting meats, chicken necks etc in my fridge so there is never a night when I am out of foods.
If you cant be bothered or are unable to get veggies cheaply a good multi vitamin supplement is fine.
You will be surprised and very pleased by the end results.