  A sample of 1161 radio galaxies with $0.01 < z < 0.7$ and $10^{21} <
L_{1.4~\rm GHz} / \textrm{W Hz}^{-1} < 10^{27}$ is selected from the Stripe 82
1-2 GHz Karl G. Jansky Very Large Array Snapshot Survey, which covers 100
square degrees and has a 1$\sigma$ noise level of 88 $\mu$Jy beam$^{-1}$.
Optical spectra are used to classify these sources as high excitation and low
excitation radio galaxies (HERGs and LERGs), resulting in 60 HERGs, 149 LERGs
and 600 `probable LERGs'. The host galaxies of the LERGs have older stellar
populations than those of the HERGs, in agreement with previous results in the
literature. We find that the HERGs tend to have higher Eddington-scaled
accretion rates than the LERGs but that there is some overlap between the two
distributions. We show that the properties of the host galaxies vary
continuously with accretion rate, with the most slowly accreting sources having
the oldest stellar populations, consistent with the idea that these sources
lack a supply of cold gas. We find that 84 per cent of our sample release more
than 10 per cent of their accretion power in their jets, showing that
mechanical AGN feedback is significantly underestimated in many hydrodynamical
simulations. There is a scatter of $\sim 2$ dex in the fraction of the accreted
AGN power deposited back into the ISM in mechanical form, showing that the
assumption in many simulations that there is a direct scaling between accretion
rate and radio-mode feedback does not necessarily hold. We also find that
mechanical feedback is significant for many of the HERGs in our sample as well
as the LERGs.
