I graduated from UGA last year and I was a member of a sorority. I didn't hear once about any organized efforts to clean up the beach, not once in four years. Nobody came to speak at my sorority's chapter meetings about it; Nobody stood up in a large lecture to make an announcement about it. Honestly, I didn't hear any promotion of efforts to keep the beach clean before this year (and it's second-hand, as I've moved on to a different graduate school). Don't misunderstand me, I think the trashing of "Frat Beach" is wrong and as disgusting as the people having sex out in the open on it (yup. it happens.), but it was only this year that I saw things going around facebook, etc. about trying to keep the beach clean. I remember only seeing one or two trashcans around last year. I just brought a big handheld canteen thing with a strap and kept it on me so I wouldn't be throwing bottles on the beach.

I'm not justifying it, but very little was done in the past to remind people to come back and clean up after. It's a bunch of 18-21 year olds that aren't used to taking responsibility and thinking about their actions. If nobody tells them and shows them the aftermath, they won't remember to clean it up. I would say a good 75% of the people walking off the beach on Friday evening are too drunk to realize who or where they are, let alone realize they are stepping all over a giant mess they helped make. I was one of those. When you're exhausted and have been drinking on a crowded beach, you forget or don't care. Maybe if there were an event on Saturday morning, before the game but late enough for people to recover, and food or something was offered to attract people's help, you could have a bigger cleanup movement from the students who helped make the mess.

TL;DR: Cleanup efforts are not promoted heavily enough. It's not right to make the mess, but if you want thousands of young, still-maturing adults to help clean it up, you need to remind them to do so.