Two issues here.
#1) Editorial use ( newspaper articles, magazine articles, books) does not require a release if the subject had no expectation of privacy. In other words, if you were on publicly owned property and the subjects were either on publicly owned property , or if they were on private property, they were plainly visible ( not inside, in a bathroom, behind a fence, or something like that). If you were photographing while "on" privately owned property, you are at the whim of the property owner. Example, if you are in Lancaster County on a privately owned farm during an Amish auction, the owners can tell you to put your camera away.
#2) Any use that enhances a business position, AKA advertising, requires a release from both recognizable people and the property owner if that is also identifiable. Using photos on your website clearly enhances your business position for you are using the photos to attract attention to your skills and get people to use your services.
There are some caveats here. The case of the Rock and Roll Fame is the most recent. A photographer photographed the structure from a public sidwalk and made posters to sell in those mall art stores. The Rock and Roll Hall of Fame sued, saying they did not sign a release. The courts ruled that the he did not tresspass, and the photo was free speech protected art. However, he could not use the photo as a promotional mailer or on his business website because that is enhancing a business interest, and he had no release.
I know what you are going to say, selling the posters clearly enhances his business interests, as he is trying to make a profit, but I guess the courts thought that "selling photos" was different than having the photos "sell the photographer"
There is very little case law on this as most issues are settled out of court. In the absense of releases, you are at risk. You may say- how will they ever find out?, so it needs to be a calculated risk, but a risk none-the-less. Some people say it is easier to beg forgiveness than ask permission, but be prepared to pay some costs to attorneys and to the other party if you can't make diplomacy and a small retroactive fee work for you.