Is honking your horn the norm here??

We're new to HP. We chose to move here because we liked the area and the community. We have a one year old who as many toddlers, naps twice during the day. Our neighbors (and their friends) honk their horn in their driveway to call someone out to the car daily. This is pretty much just under our child's bedroom window so it sometimes wakes him from his nap.
We politely asked about the honking and our neighbor told us that it couldn't possibly be from thier driveway since they never do so. Since then it seems that the honking has actually increased and today we walked out "catching" our neighbor who had previously insisted that they do no such thing. Again we politely asked about the possibility of them finding another avenue of communication, but our neighbor said "well, I don't want to go in and get them, and I don't want to call them, so I have to honk...that's just the way it is"
 We are still a bit shocked by their response.
As far as we know, it's unlawful to sound the horn for anything other than an emergency. But we don't want to start out our relationship with our neighbors with a conflict.
Is this the norm in HP?  Are we out of line to expect them to be more courteous?