I go to my LCS for FCBD, with $30 to spend on additional comics. I'm not seeing Chilling Adventures of Sabrina or Gotham by Midnight, so I grab N52 Wonder Woman vol. 3 and Injustice vol. 2. I ask one of the workers about the discounts on the trades, he says they're 30% off. I do the math on my phone, $16.99 MSRP with a 30% discount is roughly $11.90, two trades at that discount is $23.79, three is $35.70. I don't have that much, so I grab Convergence: Shazam to round that out.
I reach the cash register, he rings them up, $35.70. I say I don't have that much, so I drop Wonder Woman, shaves to price to roughly $22. I pay, I take my free Avengers and Divergence, and I leave the store feeling very confused and ripped off.
As I left the shop and drove home, I was thinking that maybe the store normally charged $20 per trade, as that's the Canadian price tag. I do the math in my head, realize, that it's not the case, and make a U-turn.
I return to the store, talk to the employees about the mistake, and the owner, the man running the cash register, apologizes and hands me a twenty. I point out that it's well over the price mistake, but he insists on me keeping it, as he's very busy.
So I'm thinking I'm gonna head back tomorrow or another less busy day to clear this all up and return the overcompensation. I don't feel comfortable being ripped off, but I feel less comfortable in my current position. Just in case, I'm not even gonna take my Injustice or Shazam out of their bags, because I never got a receipt.