Is a remote starter worth it?

At least. I wish I'd thought to grab a picture. I was too amazed. When I was at the dealership Saturday, someone drove in with a 4th generation Corolla hatchback (late 70s-early 80s).

 

That sounds terrible

The Volt will remote start off wall power or off gas power (but sometimes won’t give you a choice.)

You can also roll down your windows with the fob but I usually do it accidentally and find my car full of snow

 

There are a lot of redundant safety "features" Toyota designed on their cars mostly to cover their behind just in case of misuse. Not being able to start the engine while plunged-in is one of them. By nature of the heat pump functionality, at temperate below 14F, per-conditioning is not possible without manually starting the car and running the engine. There was a thread in which OP opted to install the remote engine start anyway and never plugged in the car during winter. Yeah, apparently if it's not plugged in. you can start the car remotely with aftermarket remote engine starter.