One way to stay frugal is to avoid ordering meals at restaurants that you could prepare at home at similar quality for lower cost.
But I love veggie sandwiches of all sorts, and particularly frequent Subway for veggie subs (it's convenient, healthy, delicious, and filling). It's pretty affordable and extremely healthy (and easily vegan), so I always feel good about getting a veggie sub. But if I did feel the need to justify frequent Subway trips financially, I would claim to myself that I couldn't make a veggie sandwich with so many toppings at home at a cheaper cost. Sure, I could make a veggie sandwich, but how much would it cost to have as many toppings as Subway puts on? Fewer toppings means less quality, less satisfaction.
But I recently realized this argument only makes any sense for a person that is 1.) single and 2.) doesn't keep much fresh produce around. But now most of my meals involve planning for a family. And now I keep a high amount and wide variety of fresh produce around the house (this week I went to a grocery store four times in five days, primarily to get more fresh produce. Fruit and veggies are vital to my current lifestyle). That means that for the most part, it's easy and cost-effective to prepare quality veggie sandwiches at home. I should have realized it sooner: the only real difference between preparing for salads and preparing for veggie sandwiches is having the bread.
So I embark on a new era. Sure, I'll still try different restaurants' veggie sandwiches when I'm out, and I'll still frequent Subway for the convenience. But I already keep loads of fresh veggies around, and now I'll much more frequently make a veggie sandwiches at home (especially when it's a meal for the whole family). I can make sandwiches just as good and better at home than I can get at restaurants, and for a much better price. It's yet another filling, delicious, healthy vegetarian meal to make at home.