Well I can at least help you out on getting a discount (or free stuff) at Starbucks, here's how it works:
Milk is well over $6 / gallon in some parts of the country, from what I gather.
I think I pay about $9 / gallon for my preferred brand of milk because I like to buy the organic stuff. ($4.50 for 1/2 gallon)
However, Starbucks (and most other coffee establishments) leave infinite milk out for customers to customize / finish their drinks.
Even though milk may be cheaper than $6 / gallon at your local grocery store, it sure isn't FREE. The FREE milk offered at coffee places is the secret here so listen up Blue.
So, suppose you want an Iced Latte. Starbucks typically make this drink very simply:
Suppose you want a Venti / Large. The cost is about $3.85, and a Venti iced latte has 3 espresso shots. Now suppose you want an extra shot, to make up for the fact that the Starbucks pushbutton machine is serving up weak espresso shots. The cost goes up by about $0.50, for a grand total of more than $4, since it seems difficult to leave Starbucks without spending over $4.
Now repeat after me:
"I'll have a quad-shot espresso poured over ice in a venti cup"
Remember, you can get all the free milk you want, turning your iced espresso drink into a latte at no added cost.
Grand total: $2.50 !!!!
For this price, you could easily add a flavored syrup (~$0.25) and still make out like a bandit. But, realize you are not doing anything shady / dodgy / wrong (morally or legally). You are merely ordering off of their menu and helping yourself to the free milk or a discount as you will.
Unfortunately, this will only work with iced espresso drinks, because for hot drinks they steam the milk. But, for those hot summer days an iced latte is a nice refreshment. I prefer mine with some mocha. And when the order is done you can still (at no cost) request extra chocolate shavings in a seperate cup.