I sent my son away to college when he was 18 in another state. He lived with his sister and her husband off campus.
We paid his tuition, bought all his books, paid his living expenses. I would make his doctor and dental appointments for him for when he was home on break, and many times I took him to those appointments. Mostly because he was still on our insurance and I had to settle the bills for it. I also wanted to spend time with him when he was home.
When he was home, he lived by our rules. He had to let us know where he was and when he was coming home because we needed to know if we locked the doors or not. We also wanted to know when he wasn't coming home for the same reason. It was a courtesy. He graduated at 23 and up until then, his rules were the same.
Now, when he went to college, it was before everyone had cell phones. But if he would have had one, it would have been on our plan.
Yes he was an adult. But he was also a child in our financial pocket, his life being financed by us so he needed to answer to us until he graduated, and got a job of his own and got off our health & car insurance, IRS status for student loans, etc.
Parents make a financial investment of their own money to send their child to college. They don't want anything going wrong to mess with that investment. So the child is accountable until they are on their own.
I do know that the college saw it a bit different, inasmuch as his grades were sent to him and we only knew what they were if he told us. I called the college once to ask that his grades, like the tuition bill be sent to us and they said no.
This is just some insight for those who keep asking why the parents seem to have control over much of Blaze's life, I.e. His phone and other things.