If they didn't want me to they'd put the machines in view of the till instead of in a different room.
I could get a 2 Litre bottle of Soda for less than half the price of their cheap knockoff, of which I'll barely drink 2 glasses, there's no need for the price hike.
They know people do it, they don't care. The option to buy a soda glass is only there for people who are too nice/don't know they don't care.
