Its your choice if you want to use it as a weopon or not, its mainly for show, sure is has an extra damage buff but thats more or less just their for the fact that is has such low durability. If your really trying to fight though, use your diamonds, thats what their for.
If you want to take this debate to another level I can, what your currently asking is for a durability buff for 1 category of tools . This would involve coding a whole new system because durability modifications dont even exist as far as I've seen on bukkit (and i use to browse about 10 to 15 pages of mods a day).
If your not asking for a durability buff, then your asking for a damage buff, the problem with that is now your making it so that the people with money will dominate people who are poor, because any higher that 14 damage a swing when the next best is like 12 or 11 is way overpowered.
Then your next though is why dont you scale the damages of the weopons a bit, with that kain will have to add another damage buff to mobs, and nobody wants that, this starts causing balance issues, health modifications might need to be done (if they can be done, theirs a cap of about 200hp on the mod or something) and all of this just causes one big huge mess.
If you really think the golden whatever is underpowered or not worth it then just dont use it, some people like to walk around with golden tools and dont mind the low durability loss, the golden tools are for them to have fun with and for wasting 10c they get a slight damage buff, simple as that.