1. hookers to offer their services
2. ignorant jackasses as a slack way to say "I love you"
3. ordinary people making references. most users think they are referencing South Park or Family Guy, but actually both of those were referencing Full Metal Jacket(#8 movie of all time according to sanyosuru). A hooker uses this phrase becuase her English is bad, and all she can say is "Sucky-sucky, 5 dollar. Me love you long time. Too long time." South Park has Eric as Vietnamese hooker, exactly as in the original. In Family Guy, Peter says this because it is the only English he thinks the Japanese baseball player will understand, and he can`t afford to pay for him.
2. ignorant jackass: me love you long time
3. synDicate: dude, did you see that episode where Peter is like "Me love you long time" that was great! They are so original.
me: no, that was a reference to full metal jacket