  High-energy photons emitted from gamma-ray bursts (GRBs) are subject to
pair-production interactions with lower energy photons, leading to an effective
optical depth. In this Letter, we estimate the opacity resulting from photon
fields located at various distances from long GRB sites: that of the binary
companion to the massive stellar progenitor, that of the star-forming molecular
cloud containing the GRB, and the total photon field of the host galaxy. The
first two photon fields are found to be transparent for most reasonable sets of
assumptions about these systems. In the case of galactic radiation fields, we
have performed several numerical simulations to calculate the expected
opacities for different line-of-sight geometries through the host galaxy, and
include a full accounting of the infrared radiation produced by the absorption
and re-radiation of starlight by dust. The optical depth for GeV gamma-rays,
due to direct starlight is less than unity for all host galaxies. At higher
energies, $>$10 TeV, a spectral cutoff can occur due to the rapidly increasing
number of mid- to far-IR intra-galactic photons reradiated by dust. Photons in
the extragalactic background light therefore remain the only relevant source of
photon-photon opacity for ongoing GRB observations with Fermi LAT, and
potential future detections with ground-based gamma-ray telescopes.
