On the subject of batteries, I've actually had lots more battery power at night after installing the fridge. They get a better charge with the extra power flowing through the system during the day.
I had observed my charge controller undercharging batteries when load was minimal before, so I'd come home from a trip and that night would have only half the usual power. When that happened the absorb stage spike was very tall and very short, and the batteries sat in float all day at a relatively low voltage.
I've read that higher lead acid float voltage can improve their charge, but of course it also risks damaging them. Hopefully whatever effects the fridge is having indirectly on the batteries are good for them long-term.