Perhaps in the Chinese culture periodically standing up and jamming a Man-pon up your ass in public is less embarassing than audibly farting. However, I'm guessing that sales will lag here in America where public anal penetration is slightly more inappropriate than flatulence.
I especially liked the part about putting a cotton ball soaked in your favorite perfume inside it to counteract any unwanted scent that may accompany the fart. This guy has really covered all his bases here. The only problem is the next time I see somebody in the library jam a dildo in his ass and suddenly I smell lavender I'm going to put two and two together. Man, that guy will be so embarassed that I know he farted!