Nacho, the cost for the stock parts vs the beefier C-body pieces is essentially the same in the US (same with the time to install). So if someone is replacing worn originals, it just makes sense to upgrade. And since dealers would routinely snap off the grease fittings, you probably need new tie rods.

My thought as to why you would want to upgrade on a non-performance car would be for added safety in the event of a collision or other road hazard. The biggest risk would probably come from the tie rod end ripping free of the sleeve. I am guessing you'd rather retain control of your car if at all possible - for me it's "cheap insurance."