I've got one with the chocolate in it. Tins are quite collectable and there are interesting ones from the Trinidad & Tobago, S. Africa, Australia, N. Zealand the UK and different cities within too. You can find them for mostly WWI but there are some for WWII. There is even a new one given by QEII to the troops in Afghanistan. It's still available on the Fortnum & Masons site.
The WWI tins are easy to find and many of them have the cigarettes etc. inside them. I've never seen one with the contents to the Indian troops inside them though.