No it doesn't - printing out free QR codes is the equivalent of just handing out free quarters. As the OP you have no idea who that person is, or if it's 1 person or 10 people. You at best only know how many times it was used.
Worse is, you don't want a QR code that can be reused for free games - because otherwise that code is basically a hole in your coinbox. So that means QR codes need to be limited used... that means making QR codes for promos on receipts can't be static they need to be dynamic. To be dynamic means integration between whatever is generating the QR codes and the thing printing them. Has stern talked about what POS systems they are integrating with and how? Notice talk of any of that or partnering??
So that leaves stern's current pitch as printing out static coupons... which everyone should be familiar with the limitations of a paper coupon and a teller (the machine) that is completely ignorant of the buyer.
As an Op it would be cheaper for me to just tell the bartender to give each new person you see an extra $1 and tell them to pick any game to play... then to spend $2k to update my machines to have a scanner to do basically the exact same thing.
They could have static printed out coupons that the buyer redeems with their APP... and then had the APP tell the game what to do. Then, you have a profile, you have a backend that can validate if this player can use that coupon again, you have tracking of who is using them, you have motivation and attach for people to get your App. I don't need fancy dynamic codes... I don't need to worry about excess... in theory I don't even need to involve the location if I didn't want to. And I've have metrics on all the use, and I'd know who my users are, and I'd have actual metrics on how the promotion is working towards driving additional sales (because I can tell who used a promo and what their future sales are).
Saving trees isn't the only reason people push their promotions through their apps these days!!
All of that goes in the toilet when you instead give out anonymous coupons in an effort to avoid using a phone/app.... and insult to injury charge people $200/machine to participate.
QR codes are not secure in any fashion - they are a simply a shorthand to something else... if you don't link it to something known or trusted... it's basically just an open door. This is why you should always be linking back to your profile, even in the case of promos. And if we are tying to a profile, you probably have your phone or your card.
And everyone is moving to using your app as your 'membership card' because of the advantages it has.