Yes, we're the same with parking outside and yes it has been an issue at times over 2 winters.
In freezing rain or if it's forecast we now don't charge - not worth the battle. That's the worst as it gums up the area inside the charge port where the hing goes and it's all plastic...
If it's just snow it hasn't been a huge issue. We get in there and dig it out with a finger before closing if we have to.
Sometimes when something is built up a little in there and we can't dig it out easy we will close the flap but not force it to latch all the way just so we can get on our way. That hasn't caused an issue yet.
I'm on the lookout for a commercially available cover. I saw one somewhere when cruising the interwebs but forgot where. I will be trying to hunt it down again.
2018 Pacifica Hybrid - In Canada Eh!