Create a temporary tire fix. In most cases, Tire Repair Tool Kits are designed for a temporary fix, meaning the puncture repair should hold long enough to get the car to a garage for a permanent replacement. This makes a kit a good alternative to a traditional spare, especially when multiple tires are flat.
Save money on replacements. A puncture isn't necessarily the end of a tire. While larger holes tend to require an actual replacement, smaller punctures can be effectively sealed with the correct kit. When done right, the permanent fix can be more than enough to keep the tire running until normal wear warrants a replacement.
Learn a new skill. Tire repair isn't a skill just for drivers. Anything with rubber tires, from bikes to wheel barrels, can experience a flat. In most cases, the repair process is the same. This means the skills you learn by using a simple repair kit can be applied to different types of vehicles.