It also prevents grout trapping in the texture. However, this is easily cleaned. Actually the iron oxide pigments used in concrete products do not fade. Nor do the colored clays in clay products. The appearance of fading is actually from light efflorescence and can be stopped by sealing with the appropriate Aldon sealer.
All concrete products are subject to damage from acids.
However, the appropriate Aldon sealer prevents this. It also prevents traffic wear to the sealers.