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When grout is used in the crack between the tiled wall and the countertop the job will look great for a little while. Then the grout begins to break out in the counter/tile joint as expansion/contraction between the dissimilar materials puts stress on the grout line. Most tile installers prefer to finish the grout job in one trip. The cost of the job increases if caulking is involved since she has to make at least one additional trip after the grout dries to apply the caulk.
Now for my humble advice. First, during tile installation, leave a small space between the tiles and the wood surface or countertop… no more than 1/8 of an inch. Now you must make a decision… how do I seal this joint? You can either 1) try to keep the joint-in-question clear of grout and use a flexible caulk (latex or silicone) to fill this small gap or 2) grout the entire job now and apply the caulk down the road when it begins to look unsightly.
Of course there is a third alternative… you can do the job like "the pros" and grout the entire job. Just keep some grout in an air-tight package for the inevitable touchup down the road! This is not as weird as it sounds. Sometimes the appearance of the caulk is not acceptable making periodic regrouting preferable… the home repair equivalent of "planned obsolescence".
You must also choose the correct caulk. Latex caulks can be successfully applied 24-48 hours after grouting while silicone caulks need full drying, so a wait of at least 3-5 days is preferable for proper adhesion. If you use a latex caulk, be sure to choose one designed for kitchens and bathrooms. They include a stronger mildewcide and are more water resistant.