In general, carrying a katana as a regular item for personal use in everyday life is not common in most parts of the world today. The katana is a traditional Japanese sword with cultural and historical significance, and while it is still revered and admired, it is primarily used for ceremonial purposes, martial arts training, or as a collector's item.

In contemporary society, laws and regulations regarding weapons vary from country to country and even within regions, but the majority of places have strict regulations on carrying bladed weapons, including katanas, in public spaces. Such regulations are in place to ensure public safety and prevent potential harm.

That being said, there are enthusiasts and practitioners of Japanese martial arts, such as kendo or iaido, who may own and use katanas for training and competitions within the context of their respective disciplines. These individuals may transport their swords in appropriate protective cases when traveling to and from training facilities or events.

It's important to note that the information provided is based on general trends and may not apply universally. Laws and cultural practices regarding weapons can differ, so it's advisable to familiarize oneself with the specific regulations and guidelines in the relevant jurisdiction.