The USA may take the concept of "collection of laws bundled together" a bit too far for comfort, but such concept implemented with more moderation is a good one, I may even say a necessary one. Laws often have dependencies between them, a change in one "concern" may affect another negatively, or may simply not bring the desired good without changes to the other one. So it makes sense to bundle such concerns into a all or nothing deal. A simple example would be a bill to build a shipping port in a remote location being bundled with a bill to build a railway and a roadway to said remote location; if one is passed without the other you end up with a useless port or a useless road/railroad.