
Looks as good going is as it does coming back out
After you've stuffed your bloated face and fed your 3 chins an Indian dinner then chased it down with a few beers, 1/2 a bottle of red wine and a whiskey chaser, you may be feeling a bit queezy, you may have even gotten rid of that poison in nature's own way. Many Japanese have a high prevalence of vomiting after the ingestion of alcohol. With one of the highest consumption rates of alcoholic beverages in the world it's easy to see why.

" I gotta go to work in 5 hours"
One factor in the high incidence of Japanese vomiting all over the place is their body size, their drinking rate (how much and how fast), and whether they have a full or empty stomach. If you drink faster than you metabolize it you will get drunker faster. So depending on how much and how fast he is drinking, your Japaneses friend isn't doing any good throwing up. He would be better off drinking slowly and in moderation rather than throwing up. Vomiting can damage other things besides just working to get the alcohol out.
Someone's wasted ramen dinner
Perhaps he needs to learn why he is drinking in the first place, and why it is so appealing to him. Japanese Beer is also at least 5% and goes up to 9%. It tastes way better than shitty American swill as well. It's also culturally acceptable to vomit in public and shit one's own pants after a night on the town. Ladies who had a little too much to drink often wake up being raped by Waseda University students but that's another story.
It was pretty fuckin' tasty at least, but it sure is gonna burn on the way back out
Fortunately, the high rates of alcoholism coupled with the high rate of alcohol intolerance have created many jobs cleaning up the mess left behind. 
53 year old Atsuyuki Nagaoka says, " Don't look down on me , White Devil. I get about 85$ an hour for this shitwork"
While low status, these jobs on the JR Lines pay upwards of 3,000 yen per hour to start and after only 5 years get up to about 9,000 ( 86$ USD) per hour. Shinjuku Station has 4-6 full time staff whose job it is to clean up after drunks. They don't have to do anything else. They sit in the drunk cleaning crew lounge and watch tube and play cards until they get the call. The other cleaners ain't allowed to clean up human excrement according to JR rules and Japan's strict hygiene laws that require lots of training and exams for even the easiest jobs.
This very untalented crew only work from 6pm-2am and get a plush, free room in the station to crash out in after they missed the last train home. Other stations have 1-2 staff who fan out to service several nearby stations when called. They also get an free pass for all JR and Shinkansen lines nationwide. No other JR staff other than the top management get this perk. The overnight vomit cleaning crew has the lowest turnover in all of JR. There is a 3.5 year waiting list just to take the exam for this job. You are better off getting another job at JR and trying to get promoted from within.
Another elite special branch of the JR maintenance squad is even more exclusive. The waiting list for cleaning up human remains due to accident or suicide is only 2 years. That job pays 12,000 yen per body with a 350,000 yen per month guarantee for waiting around. They have to service a lot of stations on their line though. The bad part is that they need to have a 4 year university degree in a related field like biology or some shit. They also have to wear white lab coats, face masks and rubber gloves to look more medical like and official. During the melancholy months of December and January these lucky, unskilled workers can sometimes clean up 3-5 bodies a day. During the huge crash in Kobe a few years back where about 100 people died the human remains workers made enough to take the rest of the year off.

Thanks for keeping the Japanese economy booming, Kenji.
So, don't feel bad for the guy who puts saw dust on that mess you've left behind or perhaps stepped in and taken home to his hot, much younger than him wife. He has one of the most sought after shit jobs in Asia and he's mackin'.