Was this little boy rude?

We just moved to a neighborhood a few months ago, and there's a boy my son's age across the street. They play occasionally, and the other day he came over and rang the bell and asked my son to come out. My son had no sooner gotten on his shoes and walked out the door then the boy's dad called him and he took off running home--no "goodbye" "see ya later" "my dad's calling" "kiss my ***" NOTHING. The kid just took off. My son has been tentatively diagnosed with Asperger's Syndrome (full testing isn't until August) and when this happened, his little face just crumpled. This other boy also has a friend who goes to the same school as this neighbor boy, and a few weeks ago he came over and asked to borrow my son's four-wheeler, but said (not in so many words) that he didn't feel like playing with my son. Are these children rude, or do you think they're normal kids (ages 8 and 10) and I'm just being overly sensitive and judgmental because my son has special needs? My husband thinks I'm overreacting, but I think these childrens' behavior was exceptionally rude. Even my boys (who are FAR from perfect) would have at least said bye, I can't play now, or something to that effect before running home. What do you think?