Because that was a good approach given the details in your original post.
You have text content for the company name so the logo is in fact just decoration and adds nothing to the semantics of that element and therefore a background image is suitable.
If you want the text and logo as a link then you can do it much the same but just with an anchor thrown into the mix.
I hardly think you want the address clickable but if you do then you can put an anchor around the whole thing as Ryan suggests although I would put the logo image inside the h1 and not orphaned in no-mans-land (just a personal choice).
There are many ways to do this and every time you change the requirements then the previous approach may not be suitabled. When you have new requirements mention that the requirements have changed and continue the discussion in the relevant thread so others can see what has gone before (or if its a substantial change requiring a new thread then at least link to the old thread to give viewers a hint of what went before).
CSS is always about what comes next and we can only code for what we see now.
I took your advice and changed the Logo back to a background image to tie things together. I also kept having the Company Name and Address all wrapped in an anchor. As I see it, the Logo, Name, and Address all look like one unit similar to “letterhead” and so I think having them all be one link makes the most sense.