with the 5 indicated being the full price
... only the 5 is in fact not incidated as the full price. The minimum price is 4.99 without the discount and it was 2.49 with discount. For both projects you linked, the suggested price is 5.00.
The price indicated is the price above the little box where you can write the price.
It took me a while to find a current example on sale, that uses a suggested price. This option is not commonly used on paid projects.
https://raou.itch.io/top-down-interior-tileset
Download this asset pack by purchasing it for $18.00 $4.50 USD or more.
$5.00
Try entering a price below 4.50 and you will get this error message:
You must pay at least $4.50.
The $5.00 that is prefilled in the box is a suggestion. You need to look above, where it says, $4.50 or more.