I spoke with the owner of Doo’s for Dogs today, and she said that Doo is indeed short for hairdo. The dog logo was created by a designer and is based on a photo of the owner’s dog. The owner said she and the designer together agreed on the end result. My sense is that, for the owner, the most important aspect of the design was the overall image. I didn’t ask whether or not she considered the correctness of the name of the business (not to mention the play on doo-doo, which may be the bigger sin — or not, depending on your viewpoint). I was simply grateful that she took the time to speak with me. The place sounded busy over the phone — dogs were definitely getting ‘dos!
So there you have it: a spelling mistake and the ubiquitous addition of an apostrophe s. So many storefront signs include the apostrophe s (We Sell CD’s and DVD’s!) that people would probably think signs without them were incorrect.
Doo’s for Dogs vs. ‘Dos for Dogs. My choice would be to go for the correct ‘dos but to use lower case letters: ‘dos for dogs. To me, the lower case letters make ‘do more recognizable as the short form of hairdo. Using the correct version with capitals would probably cause some nerd out there to comment, “Disc operating system for dogs? That’s awesome!”