I've had the pleasure of speaking to people who have actually said that - or something along the lines. "Why are you studying Japanese? Don't they teach English in Japanese schools? You can just speak English with Japanese people."
I enjoy introducing English-only speakers to "The Chaos" by Gerard Nolst Trenité. It gives them a good idea of how terrible English can be - as even people who consider themselves "fluent" in English will struggle through the poem and mispronounce many of the words. ( http://ncf.idallen.com/english.html )
As a person that is not a native english speaker I find english extremely powerful language, with hundreds of nuanced words that convey different aspects and facets of seemingly same ideas - like emotions! Thesaurus raids can be fun! As well as reading well written, witty prose (#Fuck poetry)
I also love how it can compress complex ideas into one word - it actually makes speaking in my native tongue hard, because a lot of such words siply do not have translations (or just are translated into way more general ones)
Or in other words: 说话像一个男人谁不说第二语言