Wagamama and Green Teas

I had lunch with a friend at Wagamama last Saturday. We were amused to find that Wagamama charges for water but gives green tea for free. Given that one just need to turn the tap to obtain drinking water but need to add green tea powder to hot water to obtain green tea, we believe that Wagamama should do the exact opposite (i.e. charges for green tea but gives water for free). We tried to come up with several theories to explain the reason behind Wagamama’s practices. Here’s 2 of them:

1)The demand for water is way much higher than that for green tea in London. It thus makes perfect sense to charge for something that has high demand and provide something with low demand for free.

2)All Wagamama staffs probably drink green tea to quench their thirst while working. Since Wagamama has to provide green tea to its staff, it might as well extend it to the customers for free. Afterall, what is the problem of producing slightly more green tea?

If any of you have more plausible reasons, do share them here.