I'm not a native speaker, sometimes I was like, I understood every words but still could not catch the true meaning.
I know it is stupid, but can anyone enlighten me on what Sam was thinking in this scene?
(In hotel room)
Dean: Man... Hope I die before I get old. Whole thing seems brutal, don't it?
Sam: You think we will?
Dean: What?
Sam: Die before we get old?
Dean: Haven't we both already?
Sam: You know what I mean, Dean. I mean, do you think we'll still be chasing demons when we're 60?
Dean: No, I think we'll be dead... for good. What? You want to end up like Travis? Huh? Or Gordon, maybe?
Sam: There's Bobby.
Dean: Oh, yeah, there's a poster child for growing old gracefully.
Sam: Maybe we'll be different, Dean.
Dean: What kind of kool-aid you drinking, man? Sammy, it ends bloody or sad. That's just the life.
Sam: What if we could win?
Dean: Win?
Sam: If there was a way we could just... put an end to all of it?
Dean: Is there something going on you're not telling me?
Sam: No.
Dean: Sammy.
Sam: No. Look, I'm just saying... I just wish there was a way we could... go after the source. That's all. Cut the head off the snake.
Dean: Well, the problem with the snake is that it has a thousand heads. Evil bitches just keep piling out of the Volkswagen.
Sam: Yeah. Guess you're right.
(In Ruby's car)
Sam: Okay. I'm in.
Ruby: What changed your mind?
Sam: I don't want to be doing this when I'm an old man.
So, I see...
Sam wanted to grow old with Dean.
Since he took Bobby as a positive example of aging hunters, he prospected that they could keep on hunting Monster of The Week when they are old, like their friend, Bobby.
Only he did not want to deal with those up/downstairs, so he was responsible to end the angel-demon battle first, as in killing Lilith with all means.
Is that what Sam meant?
He still wanted to enjoy hunting with his brother like they did in S1, but not being torn between heaven and hell anymore?
He did not mean to completely quit hunting, and live an apple pie life, right?
'Cause in 4x08 Wishful Thinking,
Sam already said he did not wish for going back to their old lives,
that he did not want to be a lawyer with a nice car and a white picket fence.
All he wanted is Lilith's bloody head on a plate.
Also, in 3x15 Time Is on My Side
Dean: Well, you're not helping. You forget that if I welsh on this deal, you die. Guess what? Living forever is welshing.
Sam: Then whatever the magic pill is, I'll take it, too.
Did Sam think about growing old / living forever with Dean before? Which is romantic♥.