This phrase is applied when someone has their priorities so out of whack that they'd cry for a dog if it died in a movie but have no problem watching a dozen or more people getting killed, even though everyone knows that animals are never mistreated on a movie set.
It also can be applied to extremist groups when they talk about saving an animal's life but allowing a human or group of people to die.
Usually said in a pseudo-dramatic or condescending sense, the phrase is used as a way of saying in a sarcastic manner "Your priorities are all messed up!", because at least a nice woman you can mate with, what are you going to do with a dog?
John: "I'm watching this movie. It's sad. They killed a dog."
Jack: "Wait a minute. The killer just hacked 15 people to death with a chainsaw ten minutes ago and you're okay with letting them all die but 'don't hurt the doggie!!'?"
A general putdown on someone who is excessively annoying, obnoxious, rude, stupid, or egocentric.
It comes from the idea that the fans of the Steelers of the National Football League act like they personally are better than everyone else because they root for a team that won six super bowls, even though the fans of the other 31 teams in the NFL don't care about this fact.
The problem becomes compounded by the fact that no matter what you say about this team in criticism, the response will somehow involve this idea of the team winning six super bowls.
John: "That guy is so full of himself. He's like the Pittsburgh Steelers".
An ice queen is someone who is not only very unsexual and unaffectionate, but also can be very cold to her prospective date during the date. Traits include: throwing around barbs even after it's funny and just being rude, vindictive and cruel.
"Myra is a total ice queen! You better avoid her like the plague!"