This game is the best. I currently work in Retail and I would have to say; this game hits the nail right on the head... and I can strongly recommend this game to anyone who is working retail.
I would love to see a Cashier (mini/sub game) mode or as a mission that is randomly called out via text box.
Have a text box appear with text detailing a random number of customers in line; players would have to drop their current task and take care of cashiering while avoiding getting stopped by customers before their sub timer runs out enroute to the registers.
While on till, players have to be accurate and efficient, after three mistakes players loose; mistakes include: Excessive and insufficient change back to the customer, missed item while scanning/ customer leaves without paying for an item, and unbagged items.
Players would have to scan and bag items. appropriate payment type (Cash, Check, or Credit Card with Coupons), with each Customer to ring up another sub timer will count down and if a player is too slow the game over.