North Korea's Minced Beef and Bread

Back in July we ran a post about the evil "US imperialist" fast food now available in North Korea.
Burgers, called "minced beef and bread" to avoid any connection to American fast food, are the biggest attraction along with fries, crispy Belgian waffles, fried chicken and yes, hot dogs.
The restaurant buys soft drinks from local shops that cater to the diplomatic community and resells the beverages in paper cups.

Since Samtaesong opened its doors in May, customers, including foreign students from China and Russia, have been standing in line to place their orders.
Prices may be set in euros, but US dollars are accepted as payment.
A "minced beef and bread" costs 1.20-1.70 euros (1.77 to 2.50 dollars) and about 300 are sold each day.
The most expensive item on the menu is the crispy fried chicken at slightly under three euros.
North Korea's per person income was estimated at just over 1,000 dollars in 2008,
a whopping 2.74 dollars per day.
But that doesn't seem to be hurting business. There's a plan to open more Samtaesong outlets in the country.

Everything sounds great, but we just have a few observations:
1. How many burgers can they possibly stack on that grill at one time?
2. What's up with that can on the grill?  What is that? Why is that?
3. What's going on with the girls and the hair treatment in the second photo?