Yeah, you guessed it. The cost is your health. Actually it's a lease. Pay cheap now, you'll settle the bill when you hit your forties.

I've got a Chinese friend who always uses the fat end of the chopsticks.  He says he doesn't trust what's been in another's mouth.  

This proves to me that he thinks.

5毛钱一双筷子

I bought same (4) chopsticks for 12 Rmb in Urumqi Carrefour a month ago. They are not wooden. They don't float in the water. Something heavy is inside. I don't understand, how they can cheat on friggin' chopsticks. Isn't that something authentic to China (Asia)?

I bought another pack of 20 chopsticks (Suncha) made of bamboo, light brown colour (no paint) for around 25 Rmb. Since I'm single, that purchase is nearly for lifetime.

You can dip them in the bleach for few hours or overnight. Paint should go off.

Each year, the equivalent of 3.8 million trees go into the manufacture of about 57 billion disposable pairs of chopsticks in China, according to statistics from that nation’s national forest bureau.

In the U.S., Americans threw out 31 million tons of plastic -- including plastic utensils -- in 2010, making up 12.4 percent of the nation's municipal solid waste. 
In India, it is very important to remember only to use your right hand when eating. Your left hand is only used for more personal purposes such as wiping your ass.