  We consider the quenched and the averaged (or annealed) large deviation rate
functions $I_q$ and $I_a$ for space-time and (the usual) space-only RWRE on
$\mathbb{Z}^d$. By Jensen's inequality, $I_a\leq I_q$. In the space-time case,
when $d\geq3+1$, $I_q$ and $I_a$ are known to be equal on an open set
containing the typical velocity $\xi_o$. When $d=1+1$, we prove that $I_q$ and
$I_a$ are equal only at $\xi_o$. Similarly, when d=2+1, we show that $I_a<I_q$
on a punctured neighborhood of $\xi_o$. In the space-only case, we provide a
class of non-nestling walks on $\mathbb{Z}^d$ with d=2 or 3, and prove that
$I_q$ and $I_a$ are not identically equal on any open set containing $\xi_o$
whenever the walk is in that class. This is very different from the known
results for non-nestling walks on $\mathbb{Z}^d$ with $d\geq4$.
