It is artifical and does seem stupid at first, if one is not accustomed to it.
But there are a few things to consider:
Nobody is being deceived. Everyone can see the robes going from the stack > to the laypeople > to the monks > and then back onto the same stack.
Everyone knows it's just a symbol, and a waste-free way of giving a donation.
It's a nice tradition, in which we remember the Buddha's time when robes were hard to get, and how fortunate we are today.
By giving robes we make a remembering-connection with the teachings of the Buddha where other robes were given.
We could just give $$, but by buying and giving recycled robes we make that connection with the teachings and ancient times.
So it does seem strange and silly, but there are reasons.