Yes, police have a lot of power and can sometimes get away with doing illegal things. The probability increases when the victim is somehow marginalized. Most people won't bring it to court, but if the search is fruitful, it's guaranteed to end up in court.
The increased use of car and body cameras makes this particular abuse harder to get away with. A request to search denied followed by a call for a dog, followed by unusual delays recorded on dashcam leads to a challenge even the most overworked public defender would raise.
The success rate will not be 100% when the searches actually finds something illegal. Most of them will take a plea, but on occasion, one won't.
I'm not saying it never happens, but the legal risk is too high for most cops to do it often. They may try to get you to think they will, but it's usually a bluff.
The increased use of car and body cameras makes this particular abuse harder to get away with. A request to search denied followed by a call for a dog, followed by unusual delays recorded on dashcam leads to a challenge even the most overworked public defender would raise.