the only bars I have that were "drilled" for internal cable (housing) routing are late-era Cinelli "Top 64" that are not actually drilled but punched with 2 oval (capsule-shaped) holes...and those holes are punched in the reinforced sleeve, too.
The bars are also anodized (blue-ish color) and I wouldn't be surprised if they were heat-treated aluminum, too.
With all that, this is something (punching holes in their bars) Cinelli didn't do much of or for long, and I guess the legal division might have had something to do with that.