I live in a border down. There are two border crossings here. I recently had something shipped to me using UPS as the courier. I did not engage the shipping. I did not pay for it. It was something that someone owed me, and they made these arrangements entirely themselves without my involvement or input.
UPS nonetheless wanted to charge me around $100 for "customs brokerage fees." I told them no way and that I would self-clear.
I had never self-cleared a package before, so I was in very new territory. But I was highly driven by my desire to not give UPS one penny of what I felt was a ransom demand (they were holding my property hostage unless I agreed to pay them money for services I did not solicit).
In order to self-clear, you just have to take a slip of paper that UPS gives you to your local CBSA office (Canadian Border Security Agency). The offices for these places in my city are at the border crossing.
I took a wrong turn, because I had no idea where I was going, only to find myself crossing over to the USA with no ability to turn around because it's one-way.
I did not have my passport with me!
The US border patrol officers were extremely nice. They assured me that it happens all the time. They had to pull me in and did search my vehicle but I was sitting in immigration for all of 20 minutes waiting for them to do some paperwork. As soon as they found out that I hold a valid passport, I just didn't have it on me, they gave me a visitor's visa and sent me on my way.
This was a week ago.
So yeah ... we hear horror stories. The news is alarming. And one single anecdotal data point does not statistics make.
I just want to offer a counter example to the horror stories because the news cycle loves to get people freaked out. That's their job.