Their support team responds to (numerous) requests from multiple users about it saying roughly "cannot be disabled without buying but we'll let engineering dept. know you want that". Yeah, right, like it's an engineering problem.
Worse yet -- if you have >1 Nest camera, and you DO pay for Nest Aware on some but not all of them, the banner still shows up on any camera views you aren't subscribing for.
It's really crappy because the bottom bar is a fixed height, so if you shrink the browser window it can easily take up >=50% of your viewport. Absolutely absurd -- only option once you have their hardware is to use a plugin/bookmarklet to kill the nag bar's CSS. =(
I'm never going to leave a review.
My review will of course focus mostly on my most recent experience with the app, which was "getting annoyed with an obnoxious pop-up". I hope that this discourages app authors from doing that.