Amir, no one should have to be on the look out for attacking dogs in the same way they should not have to be on the lookout for dangerous drivers, or broken glass or all of the other inconveniences and dangers we face every day. Teaching us about personal safety and how to keep ourselves safe is a realistic way of dealing with an issue which is international. I should also point out that despite the fact that you will rarely, if ever, see strays in London these days because of education, enforcement and legislation, there has been no reduction in dog bites. This is because very few bites are caused by unknown dogs. Most people are injured by their own dogs or dogs they know.
The reality is that all developing countries and even some developed countries have many social problems, one of them being stray and latchkey dogs. As long as people believe that their dogs are different and therefore should be allowed to be of their property without supervision, the problem will continue. You'll find that most of the 'stray' dogs in San Pedro are owned, but until responsibility can be defined in law (and Belize has much more pressing issues to deal with right now), people can and will allow their dogs to wander, cause a nuisance, foul, bark, turn over garbage and will still consider themselves 'responsible'.
That is why for safety's sake, we need to learn to be responsible for our own behaviour and reduce our risks of being injured. In the same way we look out for traffic or watch where we walk in bare feet.