I did this every time I re-entered the US for several years. After a few times, they took to arresting me for 4-10 hours on EVERY ENTRY, sending busses without me, making me miss connecting flights, et c. One time I was locked in a room without food, water, or medication for 12 hours. (FWIW, I'm white, a US citizen, employed, and wealthy-by-most-standards-but-not-by-HNs.)
They'd sometimes simply intimidate me, sometimes they'd make a big show about searching everything I had (not even looking in every zipper pocket), et c. In all cases they would lie to me and tell me what I was doing was illegal. (Remember: making false statements to federal agents is a crime.)
I eventually stopped after a few years and would voluntarily yield to their probing questions to avoid delays; I continued to get harassed by border guards and sent to secondary (for an additional 1-10 hours of arrest) on every entry for approximately 4 years afterward, even when answering all questions in full voluntarily. These days, they don't ask me questions, and just wave me through. I'm curious what changed a year or two ago to make them stop harassing me for exercising my rights for 24 months some time ago.
Oh, I almost forgot: one time, they digitally penetrated a Canadian woman who was my travel companion, simply because, in secondary (where we ended up because of my previous rights assertions) we both declined to unlock our phones for the border cops. They strip searched us both, and denied her entry. Denying entry is somewhat understandable due to the failure to search her encrypted device (if a bit dumb), however, sexually assaulting her and forcing us both to manipulation of our genitals is a little bit beyond their mission, in my opinion.