I have travelled in China in 2009 and I used to board D train 200kmph. There used to be a garbage collector who used to come before the station comes to PF or every 2 hrs with a big garbage bag and travellers put the wrappers and waste into it. The same should be implemented in these trains with catering facility collect garbage after 30mins serving the food. Every coach should have dustbin big size with wide mouth on both ends.