Occasionally when starting the Milk Jug Toss game on the boardwalk, a random selection of bottles will disappear. This can cause other bottles to fall if they were on top of the disappearing bottles, of which the fallen ones will not award any points even if they fall into the point zones.
I have most often noticed this while playing on US East plaza servers, and I am west-coast based, so it may be related to ping in some way.