I can provide information based on general traits associated with the INFJ personality type.
INFJs are often described as empathetic, caring, and thoughtful individuals. They tend to be considerate of others and may find themselves naturally inclined to compliment strangers as a way to make them feel appreciated or to establish a positive connection. INFJs are known for their ability to understand and empathize with people, and this can lead them to offer genuine compliments to brighten someone's day or to express their admiration for something the person has done or achieved.
Keep in mind that individual personalities can vary, and not every INFJ or any other personality type would act in the same way. People's behavior is influenced by various factors, and compliments may also be influenced by cultural norms, personal preferences, and the specific situation.