Neighbors dumping their trashbags near my building!

My neighbors next door (I don't know the culprits) developed a new habbit of dumping their trashbags at the empty land lot next to my building, mind you the garbage dumpster is only 150-200 meters away from the location they decided to dump their trash, I'm guessing one person started this trend and the rest followed dumping their trash there, so my question is, what can be done about this ? Contract Amana ? Is there a number to report these kind of things? If I raise this issue to them, are they going to place a dumpster in that new location or will just alert the garbage truck in that location to clear them ?

On the same note what's with the littering habbit of people here? I don't want to sound like a Kevin and I know there are way bigger issues to worry about in this country but I just can't seem to understand the absolute disregard people have to others, their neighborhood and the environment, why is throwing trash in the designated places seems to be a huge challenge !? Why is littering so rampant here ?