Any ideas how to deal with ping overuse?

I think it's quite a common experience that players use pings to harass the rest of the team rather than actually help.

Mostly, these harassing pings come in form of multiple pings at the same target (baron nashor, dragon, middle turret) when the team is already heading at the location or they declined the strategy suggested by the ping. (eg.: "No, we won't take baron at lvl 9").

I see this really negative effect of this - I tend to ignore even the important pings because I hear the "cling" sound every 10 seconds of the game.

However, I coudn't come with any software solution that wouldn't endanger the strategical aspect of these pings.

Trying to convince players to "Just click once, please" always fails. Some even take that to ping around the map to enrage me. I never let them know that their succeeded on that quest, however that doesn't teach them anything.

What's your experience?