Of course it's not necessary... no variants are. It's simply another way to play that speeds things up and changes the dynamics.
Is it exploitable? A little.
Some variants are necessary to make the game (more) fun or even playable. This variant is unnecessary because it does not add anything positive to the game, for me at least. It may shorten the game (not necessarily a good thing if the game is fun) but makes it less fun.
Nice to share, but it definitely isn't for me.