One would think that a company such as Hallmark would have a good proofreading department. I suspect they would not sell too many cards saying – hapPY BITRHDAY. There is an expectation that what is printed is correct.
Imagine my surprise today when spotting an apostrophe instead of a dot, as well as capital S and DAY. Not fatal to anyone. Most people will probably read as a dot as intended but that does not alter that it is incorrect. Everyone can make an error but what is surprising is that within Hallmark or its subcontractors, the sign must have been read on a screen or as printed by the graphic designer who came up with the proof; the sign maker; the people who erected the sign; and, all staff entering the building.
That suggests that these people did not spot the missing dot, the misplaced apostrophe or the capital letters. Alternatively, it suggests that they did not care as to what potential customers might think. I think that the latter would be worse but need to consider it further.