Character Advantages and Disadvantages are not symmetrical! They play different roles in the character and in the game. Most Disadvantages are about spotlight time for your character; more broadly, flaws make characters interesting.
Games like M&M 2e, Fate, and others that treat such flaws as rewarding players when they come up play out much more naturally to my mind. Instead of the GM having to make sure that a character's flaws come up enough to justify the points, the player cooperates in making sure they come up, because they only pay off when they do!