I just layed ceramic tile in the entire kitchen except for about 7 square feet where the sink cabinets will go. I did not tile this small area so I can re-route my plumbing. For the other areas where I will have tile covered with cabiinets, dishwasher, oven, etc, should I seal the grout? I am asking because a quart of grout sealer thats recommended for the grout I purchased is close to $100 and I don't know how far that stretches.