What are you selling

Here's another picture I took in Daejeon, with signs and lights as usual, but there's something different here. There is a clue in the door of this building that hints to us and winks in a subliminal manner what we would find inside. It's extremely subtle and if you don't look for it, you won't find it at first glance.
That thing is no other than a picture of a famous ping pong teacher. That's right, PING PONG CLASSES FOR EVERYONEEE! Yay. I even bet they were given for free. I would have gone in had it been daytime, but of course it was late at night, ping pong centres don't open at those hours.

Fake cross processing.