My first thought also would be, how old was he.
Both my grandsons age 10 & 11 could possibly have done the same thing. In their mind they would have been thinking neibourly, friendly, honestly trying to help. He probably ignored you the rest of the time because he might have thought you unfriendly. Maybe if you had talked to him and asked a few questions your assumptions would have been answered. We have often met some lovely families because their kids came over to see what we were all about. Just my opinion!