Had the exact same thing happen here at the start of the year and it has turned into a right mess.
The town hall refuse to install community boxes and the community(or more rightly a vocal minority of the community) are refusing to pay for them too. Six months down the track while neighbouring communities have installed boxes there is not even a sniff of one here. Correos stated they would still deliver registered letters and large boxes but only do the registered letters and not the boxes but I'm sure this is because people from the community are doing bi-weekly protests in front of the post office and town hall. I'm positive some things of mine have disappeared but can't be certain.
a) isn't there a law of some sort in Spain that says every domicile muist have a letter box? Unless I go to the post office regularly to ask (and this is difficult seeing I'm a non resident) how am I to know of any official notices that are being sent to me?
In fact it is the opposite thanks to a Kings Ruling which is the law they are citing here which basically states that if there is not enough population density then there is no obligation for a door to door postal service. Most urbs even if full would struggle to fill the numbers.
We are moving very shortly and the town we are going to has already gone through this process and reacted in a normal way about it so for now I'm happy to leave these cheapskates to it.
That said I would love to know is if in the Campello, San Juan, Alicante area there is a place that will sign for amazon deliveries and you can go and pick them up.