Why am I not doing this?

Well, you can (no pun intended). How many times have you woken up after hosting a sizeable gathering to find cans not only in the main party areas, but under and behind the couches, on top of the fridge, and the inevitable collection on the back of the toilet? It isn't hard to dump the remaining contents and throw them in a bag.
It seems like a pretty cut and dry deal – drink canned beverages, collect the cans, and eventually take them to the scrap yard. However, there are certain issues that make the business venture less than desireable for many college students.

Issue 1: Logistics
Let’s say you throw one good-size party every weekend. One good-size party may generate 15 to 20 pounds of cans (depending on variables such as what people are drinking and the vessels from which they drink).
Outstanding, now let’s do the math. Depending on the market, scrap yards buy cans at prices ranging from 30 to 60 cents per pound. Best-case scenario you’ll cash in $12 worth of cans per party. The nearest salvage yard is about 10 miles outside of Athens. Provided you have a car that gets 30 miles per gallon and fuel remains at $2.25 per gallon, you’ll be spending almost 15 percent of your earnings on getting to and from the salvage yard.

Total profit: approx. $10

From this point, your options may be:

1) Invite more people.
2) Store the cans and cash in once per quarter or month.

Both have inherent issues and that brings me to the next issue.

Issue 2: Storage = smell
Beer gets skunky and starts to stink. Unless you have a garage or outdoor storage shed, it’ll be difficult to store your loot. Even if you do have something outside, then good luck shoving 60 pounds of dripping, stinking bags of cans into your backseat and trunk. You could technically wash them all out and crush them, but, honestly, who has that much time?

Issue 3: Adding to the competition
Many of the people who are doing this have little else going on for them. Anyone who has tried to find a job in Athens knows that it’s a tough market. Add physical ailments or a criminal record to that equation and your changes decline even further.
You, as college students, technically live under the poverty level. In fact, you are even eligible for food stamps; however, these people don’t have the level of support that we receive - be it from the government, school, or parents.