"God" is not God's name. It's a title of some sort, isn't it? Scripture makes mention of many gods. Certainly, all their names weren't also "God", so it does point to the term "God" as being some sort of label. Moreover, the ancient hebrews had a particular name for god, represented by the tetragrammaton, which was not the same word as the hebrew word for either "god" or "lord". In genesis, God distinguishes himself from the other gods by calling himself the one true God, which he wouldn't have to do if God were a name of one god only or enough of a term to serve to identify him distinctly. Rather, there's a lot of text that serves an identifying purpose such as "the God of your forefathers" and "the God of Abraham" and so on. Reflecting on that for a moment, it appears that these adjectives were needed to point to this one god. In fact, in some places the tetragrammaton appears along with "God" and "Lord" as an adjective for the tetragrammaton itself. In the ancient texts that featured the tetragrammaton, the scribes replaced it's appearance with "elohim" and "adonai" ("God" and "Lord") so that no blasphemy may accidently occur by misspelling his name when transcribing (and probably also to prevent readers from accidentally mispronouncing his name) a practice which is down to today practiced by religious jews, as seen in your spelling "God" as "G_d", (although why that variation is not itself considered purposeful misspelling I have no idea, but apparently has its reason why it's considered OK to do).
Not that I'm condoning disrespect or your perception of it. But you're right about how it's become very much a part of the language. I was watching some show on TV the other night on network TV, and as you may know, there is a renewed concentrated effort to stay away from all matters they believe to be indecent. They kept bleeping out the "four letter" words, but left what would be considered by you and others to be blasphemous use of the deity's name completely intact.
The only answer, as the rest is just speculation. Of course this only applies for those who have chosen to be a believer!