Graphic t-shirts instantly reflect your personnality in your outfit.
A basic outfit (jeans and a t-shirt) can easily be full of style once you add a graphic t-shirt.
I've seen these in a lot of different stores so it's not because you're not near the store that's the most popular to a lot of people that you can't get your own pair.
Let me reassure you. I am not encouraging you to spend a lot of money on this. There are lots of easy ways to do this yourself and be totally unique. Let me know if you want me to post a video or written tutorial on how to do this DIY found on internet.
And relax. I can pretty much assure you ( pretty much ) that graphic t -shirts won't stop being in style tomorrow. They're too cool for that.