Put new tile on kitchen counters and just had this thought.
Should new grout in kitchen tile be treated preventively?
In my opinion, yes. All grout should be sealed.
Yes. I put three applications of sealer on my travertine backsplash (and grout lines) 10 years ago. To this day, anything that gets on the tiles or grout, wipes off with one or two swipes with a Mr Clean Magic Eraser :)