1st thing is, I wouldn't assume it's not grout. I'm doing one now, and have done many, that is/was grout and virtually impossible to get out without a grinder with a diamond blade. Secondly they make the matching caulks in all the grout colors (sanded and non-sanded). They will require some periodic maintenance though. I have also used a product called Latasil that I've been pretty happy with when exact color match to grout is not an issue.