Then don't list the $5 option as 50% off?
This isn't 50% off. This is a different pricing threshold.
50% off would be getting the $10 access for $5. What you have done is added a $5 option, then deceived your customers by telling them it's 50% off. No it isn't. You're selling a different price threshold at 0% off.
Very underhanded way to go about selling your game.