One such incident is that of the beaches of Bali. I'm not going to pretend that I know anything about the type of people that go to Bali. I'm sure there are all walks of life and both receptacle-using and non-using visitors. Complaining about the trash brought onto the beach from faraway places while on vacation, however, should not be cause for complaint to your local hotel...it should be a rude awakening that everything you do impacts something else.
The trash washing ashore is unlikely a product of the beach where it has landed. It is much more likely that it came from far, far away.
It's also unlikely that it was one big truck dumping something into the ocean. It's much more likely that it was individuals like you and me, leaving a plastic bottle behind after our trip to the beach, throwing trash out our car window instead of waiting until we got home.
So if you happen to see the side of the road on the highway near you, or your beach is littered with someone else's lack of global courtesy, use it as a reminder. Tell your friends and family and strangers about it. Get involved in community cleanup. Let visitors know that what they do affects those around them. Ask strangers who you witness doing such things to pick it up (nicely of course, to encourage positive behavior, and with a "thank you" and kind words to reward and reinforce their good actions). Maybe when people start to realize that (even though they don't care about the environment, which their garbage also affects) their own lives (and vacations) will be affected by their lack of discretion, they'll be able to make a change.
Be the change.
Help make the change.
Communicate what matters.
Pass it on.