Should there be an age limit for kids going to coffee houses?

So, not sure if this should be a blog or a rant, but something lately has been bothering me. Since I live in Los Angeles, which seems to be a horrible city for coffee (believe it or not) I am having to settle with going to Starbucks. The one I frequent most often is pretty good. The baristas are really friendly, know me by name, and have my drink ready in no time when they see me come into the store. The thing lately I have been bothered by, is this particular coffee house is down the street from not only a high school, but a middle school as well. Based on my schedule nowadays, I have been stopping by around 2:30 - 3:00. This seems to be a bad time, for school let's out at this time. I find my coffe place full of rude, disrespectful kids. Most of these kids seem to think it's just a "cool" place to hang out and just loiter around. Others go inside and get all in the way, getting only water, if anything. But there are a few who stand there forever ordering ridiculous coffee, hot cocoa, misto combinations. Now, I know I was drinking coffee at an early age, but don't remember actially visiting a coffee shop until I was out of high school.

The question I propose, should there be a minimum age set for people to go into coffee shops? Would it be bad for the company to set such a restriction?