I noticed this too. I used approx. 3GB per month previously, max maybe 5-6GB on a vacation. Now I'm using at least 1GB per day. ha-ha. It's wild.
Meanwhile, I was testing T-Mobile to see if I wanted to switch and I wasn't using 1GB per week.
I posted about this in another thread, and I was told it was me using it. That may very well be, but it sure is odd that the month we get the unlimited LTE upped to 22GB I begin using 5x as much data.