If you have your receipt I would go back get refunded money Or call mgr & tell him situation Every summer drinks are $1.49 just for summer!
Its not necessarily their job to inform you on specials. Also take into consideration that the special could have been added the next day rather than the day you payed full price.
As I agree with you it would be good customer service to do that I don't think he really has to it's kind of messed up honestly
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