I was coming home from the Union Square Greenmarket on a recent Saturday, sitting on the 14th Street bus for 30 minutes as it crawled west in stop-and-go traffic. A big commercial fair had closed Eighth Avenue, snarling movement in several directions.

I’m not the only New Yorker who hates these gigantic affairs that disrupt weekend errands now that warm weather has arrived. Stores and restaurants on the shuttered avenues lose business because people walk in the street, not the sidewalk, which is cluttered with boxes and burners from tedious vendors selling the predictable greasy sausages, fruit shakes, tube socks and T-shirts. While the fairs also bring some foot traffic to those stores and restaurants, one owner recently told me business was way off on those days. Too bad if your apartment overlooks a booming sound system or if you forget to move your car and it gets towed. Better to walk if you are stuck in a cab.

So why must we suffer through this noise and litter and incredible disruption?

Most big street fairs are fundraisers for charities. (That’s how they get permits every year from the community boards.) I’m all for supporting organizations that do good work, but I don’t think the financial breakdown is a fair trade-off.

Much of the money raised at street fairs goes into the pockets of outside promoters who organize the events and get a significant take from the space rental fees. The vendors are seldom from the neighborhood.

I learned this decades ago when I was on Community Board 3 in the East Village that looked into the arrangements.

Little seems to have changed since I first wrote about this summer scourge 20 years ago. Permits get rubber-stamped annually because it’s in the name of a good cause while we residents sit and fume in traffic.

Yes, this makes me very cranky.

Don’t get me wrong. I love the little block parties on side streets where neighbors sell vintage jewelry or used books. I adore stoop sales and rummage sales at a school or community center. What I can’t stand are the commercial street fairs: They are unfair to local residents and businesses, even if held for good reasons.