Japanese people have a lot of difficulty differentiating the R and L sounds, especially in English. This is why funnily translated English that one sees in Japan is commonly called Engrish. (Recently people are calling funny English in China Chinglish.)
There's a simple reason why Japanese people can't pronounce R and L correctly. They don't exist in Japanese. It is not, as was asked of me once, a genetic defect. Japanese people who spent their childhood years in an English speaking country can pronounce both sounds fine.
The Japanese version of the 'rrr' type of sound, the ra ri ru re ro (ら り る れ ろ) row in the phonetic hiragana alphabet, is somewhere between R and L.
So, 'rice' gets pronounced 'lice', 'balloon' as 'baroon', etc.
People who make fun of this fact are ignorant, racist, mouth-breathing cretins, most of whom barely speak one language properly, and who deserve to be choked with a big wad of mochi.
Closed to comments because I'm sick and tired of deleting those from mouth-breathing cretins.