i think he is right. according to this link http://en.wikipedia.org/wiki/Lighter there are 2 types of fuel used in lighters. either naptha or butane. all naptha lighters use a wick to deliver the fuel. this would suggest all lighters without a wick or a "zippo" are using butane.
and from my experience the only difference i have seen between a bic brand and other gas station sold brands are the design and the fact that bic is simply a far better design and construction so it lasts a lot longer