Without a points handicap, it would not make sense to pay both sides of a wager the same amount when it's clear that not all teams are on equal footing. In fact, it is entirely possible for a team to lose the game in real-life but still win a bet if they only lose by less than a set number of points. Vice versa, a team can win a game, but lose the wager if they do not win by more points than what was predicted.
When betting the point spread, there is almost always a winner and a loser. However, in some instances sportsbook decide to put out a whole number such as -3 for bettors to bet on. If the final score ends with a differential of three points - no matter who wins - the bet is considered a "push" and all money is refunded to both sides since neither team covered the spread.
When you bet on the money line, you are betting on one side to simply win. Any time you see a money line, the minus sign (-) indicates the favorite while the plus sign (+) indicates the underdog. For example: Chicago Bears –240 vs. Minnesota Vikings +210. Using $100 as the base, it will take $240 wagered on the Chicago Bears to win $100. For a bettor wagering on the underdog Minnesota Vikings in this scenario, $100 will win $210. With the money line you just have to hope your team wins rather than cover a point spread. Of course, the one downside is having to risk more money to return the same amount that a point spread bet would net you.
You don’t have layers of complexity to fight through to see if your prediction is a positive expected value move (one that is going to make you money). With some simple mathematical calculations, you can figure out whether or not there is value in a bet. Even if you don’t like math and would prefer not to use it when assessing value and making your picks, it’s still much easier to “eyeball” value with moneyline bets because of the simplicity.