Nearly 9 years ago I started a job where (tldr) it wasn't practical to go out for lunch most if the time. Since then I've eaten sandwiches for lunch nearly every day at lunch. With some variations, but not a lot recently. Down sides: I do sometimes miss the chance to get out of the office for a bit. Upsides: have saved a bunch of money and lost about 30 pounds of weight without really even trying. Also I only need about 20 minutes for lunch each day (+shopping once a week, which doesn't take long since I mostly eat the same thing).