Should I talk to my neighbors about their rabbit?

Our neighbors have a pet rabbit that they let loose all the time (they don't have a fence around their yard either). Their dogs don't bother it, so it's not afraid of dogs. The other day it was in our yard. We don't mind it being in our yard, but it could be hazardous to the rabbit, since it won't be afraid of other dogs that might attack/eat it (my dog was barking at it and it didn't care). Should I ask the neighbors to keep it in a hutch? I don't want the neighbors to be offended, but I don't want the rabbit to be in danger either.