The first objective of a spread is to bring the sides much closer to a coin toss odds compared to the price for a side to merely win the game.
The Rams were priced at -182 simply to beat the 49ers and advance to the Super Bowl, requiring a stake of $182 to be risked to return a $100 profit, with an implied winning probability of 64.5%.
The NFC Championship game gave a masterclass in how point spread betting can enhance the usual money line betting, where a side may be an unattractively short priced favorite.