Finn is an idiot. He wants to name the baby Drizzle, for god's sakes – Quinn can't honestly think Finn can take care of the baby. Finn's been his best friend for years, but Puck's never lied to himself about the limits of Finn's capabilities. Quinn's just to stupid to put their baby's welfare ahead of her pride, and cough up to a dumb drunk fuck to set the baby's life on it's proper course.
(Deep down, Puck knows Finn will be ten times the father he ever could be. But he won't admit it. It's a matter of pride.)
Quinn Fabray is not a good person. Good people don't get knocked up at sixteen. Good people don't have sex with their boyfriends best friends. Good people don't lie to a guy and tell him their carrying his baby. Good people don't cut the actual father of the baby out of her life, because she's too selfish and proud to admit what she did.
They all deserve better than her. When he father kicks her out, it's like he can see right through the victim role she can't quite properly slide into: evil, evil, evil, he sees,
(An accurate image.)
Quinn looks weird when they talk about the baby – she wears a confusing expression between anger and pity. Puck won't let him talk about it; he either yells at Finn to shut up, or starts fighting because he's sick of Finn's 'whining' – because obviously, Finn has no right ask for support when he's going to be a teenage dad soon.
Sometimes Finn thinks he hears crying in the locker room after games, but he shrugs it off.
(Finn should look closer at this and ask questions, but he can't. His pride won't let him think it.)