What does 'OBI' stand for? Seriously, I don't know. I've always been too embarrassed to ask.
Additionally, what is the point of having the strip on the Japanese releases? The US RVGs don't have the strip.
I'll take a stab at this one...
I believe obi is a Japanese word for the sash that goes around a kimono (robe). But please, someone tell me is this is incorrect.
As far as the purpose? That's pretty subjective. One cool thing it can offer is to have the barcode on the obi, and not on the artwork itself, like on the JRVG series of mini-lps.
Of course, some fans as well like to roll up an obi, and smoke them... B)