The saints have, in both movies, a "as much as fits in the bag" shopping spree in a military-style armory. Both times, they only walk out with suppressed pistols, and in both instances they run into situations that needed more firepower. They could have been taken by surprise the first time, but the second time, they should have learned to grab a few automatics, if just out of caution.
Could be the brothers suffer from a borderline case of Crippling Overspecialization, because excluding Il Duce's short-barreled shotgun in the climax of #1, we never see a Saint fire anything but a pistol.
From a Doylist standpoint, there's also budget constraints to take into consideration — no one wields automatic weapons in the first film aside from the guards in the prison scene with Il Duce, who probably had them on hand from their proper line of work. Troy Duffy probably didn't have enough money to afford an armorer.
Even if the Mc Manus brothers had an Irish mother, why do they still have Irish accents? Example: one of my friends from elementary school was from Scotland, both parents with thick accents. By the time high school rolled around, he and his little brother sounded as American as everyone else in school.
I know a friend who grew up in England with a British father and American mother. She spoke with an English accent growing up. Her dad left them over a decade ago, and she's been back in America for several years, and she still speaks with an English accent. Some people lose accents quickly but others don't.
This Troper went to high school with a girl whose father was American and her mother was English (Military Brat). She'd normally speak with an American accent, but if she got mad, she'd "turn English". Our theory was that the mother was more Hot-Blooded than the father was.
They're stated to live in a poor neighborhood full of Irish-Americans, many of whom are presumably immigrants like the brothers' parents. It's not unreasonable to assume that more people in the area use an Irish accent than a Bostonian one, passing it on to their children (i.e. Connor and Murphy).
That might have been the case back in say 1910, but South Boston's changed a lot in a hundred years. The insular northern European ethnic enclaves of the nineteenth and early twentieth century simply don't exist anymore, certainly not in South Boston.
This troper watched it with her father who's from New England and according to him, no one from Boston talks like that unless they're fresh off the boat.
The deleted scene where the boys talk to their mother, she is revealed to still be in Ireland. Presumably, they were (possibly born and) raised there, and came to (or returned) to America as adults.
Considering they head back to Ireland in between movies, it's not unreasonable to assume that they take occasional trips to and from Ireland. This Troper lives in Boston, though, and it's true that almost nobody has a full-on accent.
Children of families who speak with a different accent than the general populous can also be bi-dialectic, that is, speak with one accent to family and people of their ethnic/social group and with another accent to people they perceive as outsiders. Therefore, outsiders may believe their accents 'disappear,' when they only emerge around certain people that the children identify with. Since the brothers are always together in the film, it is not unreasonable that they would keep their accent throughout.
It's stated in the second film that Il Duce was arrested just after his sons were born - possibly their mother took them back to Ireland after her husband was imprisoned?
The movie never seems to answer two big questions in the first movie. 1) Why did Rocco kill the bartender? They suggest it's just because he was a witness but it's only a suggestion. 2)Why did the three of them kill the other two guys in the porno joint?
1) The bartender knew about the setup. 2) Rocco knew them, and they were Bad People.
To be specific, the bartender knew about the setup and didn't warn Rocco. Other witnesses were allowed to flee with no pursuit.
To take the explanation for the two guys further, according to the commentary (IIRC, it's been a while) at one point they each had a scene establishing "Scum of the Earth" status for the brothers/audience and both scenes ended up cut. I think one was a pimp they'd seen beating up a hooker outside the hospital, and I can't remember what the other guy was...
When Yakavetta first realized that Il Duce was still coming, he shouted for about half a minute in Italian. Does anyone know what he said?
So in All Saints Day the brothers and Romeo have finally been arrested for their murder spree. The movies go into detail establishing just how polarizing their actions are to everyone. Assuming Smecker's plans didn't work out and the trio had to stand trial, what would realistically occur if there was a hung jury? Assuming there's nothing but mistrials, how many times would the prosecutor attempt to prosecute the Saints before giving up?