Slow People (or those who stop randomly)

Now, this topic has got to be one of the biggest things that annoy me. If you are going somewhere, go there. It does not mean that you can stop traffic by walking slowly, and yes, there are some exceptions, old people, disabled, and sometimes, crying children and their mothers.
However, other than these exceptions there are very few excuses as to why you would take forever to get somewhere.

I am sure that most of you know this scene that I am about to set out for you:
You walk down the street, your feet drumming on the pavement, you have to get to your office quickly, your boss will fire you if you are late one more time. You are nearly there, with ten minutes left to walk a five minute walk! This is beautiful. You can't believe it. The building is in your sight, however, you cannot get there. Why? A bunch of teenagers have suddenly slowed down. They all form a line, a barrier to stop you from passing and they won't let you through. Why would they do this? You have two choices:

1. You try go around them by welcoming the oncoming traffic (that's a definite no) or
2. You wait for them to walk while you slowly trudge behind them

Now, I know that some of you may not have a job (I know I don't) but if you substitute it for... oh... I don't know, getting home in time for curfew. You can see where I am getting at right?

And what is it about those people that randomly stop? If you are going to stop, can it not be towards the side where no one is walking and not in the way of where there are people who are walking? It is just so irritating.

WHY DO YOU PEOPLE NOT UNDERSTAND THIS???

I mean, I don't usually have a problem with people (well... that's semi-debatable) but when these things happen, I just want to shout at them. (I did once, but that is a different story)

I don't know if you read the whole thing or not, I don't know if it made sense, but if it did and you enjoyed it, let me know.

Thank you for letting me rant :D