I imagine they are real and that they are just trying to get rid of them since once the show is over they are worthless. The scalpers may not be aware that this is a slower time of year.
Simple.
These are same-day performance tickets, of course. The scalpers/brokers/et al bought them in advance and couldn't sell them. What do you with extra tickets that you didn't sell? Well...you have someone 'walk' them on the street. They're asking for 'less than face value' because that's the ONLY way to sell them. Better to make some money rather lose your entire investment on the ticket.
Common sense teaches you how to be savy. If it's a show like MARY POPPINS, the tickets are valid as it's not a tough show to get tickets to, which is why these scalpers/brokers/et al weren't able to sell their tickets prior to the performance date.
Now...if its an impossible 'entire run is sold-out' type of event...then be cautious -- the tickets could be counterfeit.
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