The difference is that commercially prepared foods use a lot of salt in the recipe and it gets mixed in with the food and obscured by other flavors, so they have to add a lot to get it to taste salty.
Whereas when you cook at home, you tend to add only a pinch of salt directly into the recipe and sprinkle the remaining salt on the surface of the food, where it only takes a little to overwhelm the taste buds.
For example: McD's and Waffle House and their ilk add salt and butter directly to the eggs before scrambling them, for texture. When you have them at home, you add them after they're scrambled. You generally add much less, as well.
I do like the Healthy Choice meals . . . most range from 20%-30% of the RDA for salt, max, so if you have that for lunch and have a home cooked breakfast/dinner, you're cool.