It is plausible that people tend to park next to other people's cars because they like the idea of social cohesion in public, or they might associate social cohesion with safety. They might think that parking next to another car reduces their car's chances of being broken into or crashed against.

There are several psychological and practical reasons why people tend to park next to you, even in a relatively empty lot. One of the most common is spatial benchmarking; drivers naturally use other vehicles as a physical reference point to help them align their own car between the painted lines, making it easier to park straight. Another reason is the "herd mentality" or social proof—subconsciously, seeing a car parked in a specific area signals to other drivers that the spot is "safe" or desirable. Some people also park next to others for protection; by parking between two cars, they reduce the chances of a stray shopping cart hitting their vehicle, as the carts are more likely to roll into open spaces. Additionally, in very large lots, people often gravitate toward the spots closest to the entrance or those in the shade, leading to clusters of cars even when hundreds of other spots are available. Finally, some drivers simply don't want to be "lone targets" for theft or vandalism and feel there is safety in numbers. While it can be frustrating if you purposely parked far away to avoid door dings, it is often just a result of human nature seeking order and proximity.