This used to happen to me in the mornings when I was a college student and a school bus driver. My schedule involved being at work at 5:30 AM, and I'd be biking about that early. The cops harassed me endlessly and would make me dump out my backpack for them.
I get pulled over an average of 9 times per year in San Diego, CA, but it's gotten a bit better. I've been "pulled over" before getting into my car (which resulted in me shouting at a female cop for 2 minutes). She said she saw a "suspicious object" in my hand (car keys).
I even had one officer pull me over and TELL me that the reason he pulled me over was because "when I see a black guy in a Honda Civic, that's a red flag". He was respectful about his bias and let me go, and I have to admit it was refreshing not having to pretend it wasn't happening.
I've been arrested once when, during the crash of 2009, I lost my job and couldn't keep up with the b.s. tickets. I was caught trying to put my phone on Speaker Phone while stopped at a light and subsequently arrested because of a warrant for the unpaid tickets. What I was doing - handling my cell phone in the car - was technically illegal, but the cop was being unreasonable and the warrant didn't help.
I had an interview a month later for (still) more money than I've ever made at this point (I'm a QA analyst). The company tried to hire me pending a background check, the arrest came up in the search, and they dropped me immediately. It was embarrassing, enraging and soul crushing.
The police must have been feeling the burn at that point, and they took it out on the poor people in my neighborhood until their profiling sparked controversy and an investigation (City Heights, San Diego).
Some part of police profiling is rational. I think it's is a positive feedback issue. Interactions with police due to high rates of crime lead to broken families and single income and/or government assisted households as well as a cycle of debt and poverty with the threat of recidivism or further incarceration when the money can't be paid. These conditions lead to things like poor nutrition (leading to low IQ and violence) as well as undiagnosed mental health issues and social pressures which create the very conditions that generate more police interaction. There's no way to resolve any of this while living in the ghetto.
My mom married my step-dad, a white structural engineer, when I was 4 years old. I am thankful I was raised in a healthy environment because of it. My parents went through hell being a mixed couple in the 70s, but everything good about my life is a testament to how lucky I am to have been raised outside of bad areas.
I made the mistake of choosing to live in a low income area from 2005-2-14. I saved a hell of a lot of money, but the police saw me as just another person from the area to harass. That experience knocked me down a peg, sent me spiraling into debt and left me with a criminal record. Something I never had in all my 31 years up until that point.
If you're black in America, pay the high rent. Never look back.