ok, lets go back to pre-digital, pre internet, when you had to physically queue outside a physical building to buy anything.
You are standing in a massive line outside a record shop for your absolutely favourite bands new album which is coming out at midnight.
You've camped outside the store for 5 days to get a great place in the line.
you are 10th out of a line of 500 people that goes around the block.
the store only has 350 copies.
400 people behind you in the queue walk up to the 9 people in front of you and give them 150% of the cost of the album to buy them a copy along with their own copy and they'll wait outside the store while that person goes in and buys multiple copies leaving you s**t outta luck and empty handed as the store had no max purchase rule so the 9 people in front of you bought all 350 copies.
now imagine a super market doing that with food, or a drug store with medicine.
just on moral, ethical and common decency principals its wrong, the law typically reflects the society it presides over.