Winston Biscuit I don't see Marcos Alonso's omission from the Spain squad as a shock at all tbh. He obviously chips in with goals which help his club side but defensively I just don't rate him and that is what Spain would want him for. I have also read before that the Spanish public don't like him and there is a general feeling that he should not represent the country. getting pissed up and killing someone tends to have that effect.
With Monreal you have a better defender and he can also drop in to a back 3 too. Alba is just a far better player than Alonso. Easy decision for me.
As you say Alonso is also a murderer which doesn't help.