Barring evidence to the contrary, assume "Lipton Brewed Ice Tea" as served in a restaurant or fast food joint means a mixture of liquid tea concentrate and local tap water. Note the absence of the word "fresh". The words will be found on a dispenser that may resemble urns sold to restaurants to hold tea freshly brewed in the kitchen from tea leaves and water.
Contrary evidence means old tea makers with Lipton’s name on them sold on ebay that freshly brewed ice tea. They resembled Bunn coffee makers.
I was in a chain pizza restaurant the other day. It was a Pepsico shop as far as beverages were concerned, with self-service dispensers. Next to the soda dispensers was a Lipton- branded bright yellow urn-looking device that read "Brewed Ice Tea". The handle, looking like one on a commercial coffee urn, read "unsweetened".
With no diet sodas of interest, I filled my cup with ice, then pulled forward the lever of the tea dispenser. The rate of flow of liquid was higher than could be explained by gravity feed. Then came a brief period of clear liquid, followed by more of what looked like brewed tea. Yup, post-mix iced tea concentrate.
I added Splenda, then tried it. First of all, the machine was not adjusted peoperly. I had to add more tap water from the soda dispenser station. But, the beverage tasted terrible, much as most people who post to food boards and blogs describe pre-mix iced tea. Mine seemed much worse than normal, possibly because the BIB (bag-in-box) concentrate was old.
I thought at first that Lipton/Pepsico were just trying to design an attractive dispenser. But surfing industry webites on the ‘Net indicate the manufacturers are happy to deceive us. Nestea dispensers often include a sticker indicating the product comes from concentrate. The Lipton one does not.