I don't know the situation, but I don't think it's inconsiderate to plow a street that hasn't been plowed and is impassible except by 4x4's. Granted, when you plow the street, it does tend to block driveways. But, as you said, you just have to shovel it one more time--but at least this time, your mom will be able to get out once she gets past her driveway.

The only reason we were able to get out of our neighborhood on Thursday night is because we have a 4x4, we live three houses from the exit of the neighborhood, and because after a plow plowed the other part of the street (not in front of ours) and left big build-ups of ice and snow blocking our way out at the corner, I went out with a shovel and opened up an exit for the road through that snow and ice. But I was still happy that they had done that since before they plowed, we couldn't have gotten past the corner or the subsequent corner.

Personally, if someone had taken it upon themselves to open up the road and I only had to shovel the stuff out of the entrace to my driveway, I would have been grateful.

Regards,
Craig Steiner