Ever get into an argument with a style nazi at a beer festival and not have any evidence at hand to prove them wrong? Then I've got just the thing for you.
When the annoying geek next to you starts bullshitting about how IPA was brewed especially strong to survive the journey to India, just point at your chest. And let my "IPA was not a strong beer" T-shirtdo the arguing for you. You'll be free to continue drinking beer while your new friend drinks in the facts.
I'm getting myself one for christmas. Why not do yourself a favour and get one, too. You won't regret it.