I don't get why you would be hesitant at a discounted lasering... Discounts are not the same thing as a cheaper option that costs as much as the discounted price. Just compare it with anything else you're able to get on a discount. A phone, for example. Would you think that the 500$ won't perform as well if sold for 250$? No, it will perform just the same. But a phone that costs that 250$ from the onset, that is going to usually be worse than the 500$ one bought at half off.

So, a proper lasik surgery costs 1500$ (A price I found with a quick google search). That's a bit steep. But your wife gets lucky and gets the half-off discount. Great, you got 1500$ worth of service for 750$. Now, a lasik surgery that is being offered at the 750$ normally, that would raise a few eyebrows for sure.