A friend tended bar at Summerfest this year for the first time. Overall, it was a pretty good experience and will bring in some much-needed summertime scratch. He did, however, complain on numerous occasions about how many beer buyers hassled him for not filling up the beer cup to the top.

He was trained to only fill the cup "to the black line" (or alternatively, "to the red line," depending on the cup design, which changes from bar to bar). The line marks a 12-ounce pour and is about an inch from the top of the cup. People who overfill can be let go from Summerfest because, technically, it's giving away free beer. So he was vigilant with his careful pour and in doing so, got an earful night after night.

For some reason, a lot of drinkers thought it was the bartender being a jerk and under-pouring, not that it was Summerfest policy.

"You know what, man? You're a d*ck. I wouldn't have tipped you if I thought you weren't going to fill it up," my friend reported one angry bar patron saying, a couple nights in.

Other times, people go looking for bottles of beer, which contain four more ounces of beer but are not available at every bar. My friend could see on their faces that they were weighing the decision to stay at the cup-only bar, which more often than not had a line they just waited in or walk across the sea of people to a bar on the other side of the stage, where bottles were available.

He would sometimes help in their decision-making by offering up some math. A $5 cup of beer with a 12-ounce pour comes out to about 42 cents per ounce (a cup at $5.50 is about 46 cents per ounce). However, a 16-ounce bottle of beer at $6.50 comes out to about 40 cents per ounce.

Per the ounce, it's not quite two cents more by the cup. Comparing the exact figures of .41666666666667 an ounce per 12-ounce cup and .40625 an ounce for the bottle and most people can see that the difference is pretty small.

Once you factor in how much you feel your time is worth, debating your walk over to the bottle bar – again through the sea of people who seem to be looking at and listening to the band and not at all interested in facilitating your trip by getting out of the way – and the amount of time you just spent complaining about the 12-ounce pour instead of drinking your fresh-from-the-keg beer, the minimal difference doesn't really seem worth the time at all.

Now this has got me thinking. Perhaps Summerfest should make signs explaining pour sizes and the fill line to drinkers. That way, maybe a few less will complain to the bartenders or, when they do, bartenders can just point at the sign.

The sign should maybe measure 2x2-feet and be hung on the posts at each covered bar or on the fronts of the bars themselves. Each sign would have a very nice picture of the Summerfest cup with an arrow pointing to the fill line and some copy that reads, "this is a full 12 ounces of beer."

Another suggestion would be to serve the same amount of beer in smaller cups, creating the illusion that people are getting more for their money. To me, it makes perfect sense that they would pour 12 ounces of beer into a 13-ounce cup to prevent splashing when trying to navigate through the crowds.

Most likely, if the beer cups were actually filled to the top, beer would slosh out and in the end people would end up with less beer. But this probably doesn't matter. It's always more about perception.

The signs, though, might help people see a new reality.