Sorry but they do more than just that! I personally have seen the difference with and without them. Driving hard into corners will eventually crack the welds there were the apron meets the cowl area.
To each their own I suppose!
I would also look into a brace the bolts to the top of the shocks and back up to the center of the firewall/cowl. Something similar to a strut tower brace. Something similar to this,
