I believe those who think Google reviews do not matter may be under the wrong impression. My experience is that most people do not know car washes around their area, even sometimes when they drive by. In small towns I’m sure this is different.
As a consume when I’m looking for a service and don’t have a go to place I Google around and check reviews. I’m looking for consistency in bad reviews (ie 10 1 star reviews for all different things indicates customer issue, not business issue) and responses from business (show you care).
Yelp you have a choice not to have a page, and everyone goes on Yelp to be unhappy. With Google you should get some real ratings (good ratings) just by being there