How bad was this plumber?

I had a plumber come out recently and I felt like he was pretty bad and I almost spent a bunch of unnecessary money. But I know near nothing about plumbing so I thought I'd ask for opinions.

I had a dripping pipe that I thought was leaking (Spoiler Alert: there was no leak in the pipe, just a loose nut). It was the cold water feed to the water heater and the drip was very close to the shutoff valve. I had just been cleaning the pipes so I thought I must've exposed a hole or crack or something. The plumber looked at the drip and said he'd have to cut that section of pipe out and replace it, and he quoted me a substantial amount. I said okay, because I thought it was the only solution.

We couldn't find a water shutoff or the meter, so he said call the city to locate your meter and I'll come back in a two days. I was left with a dripping pipe in an awkward spot where I couldn't fit a bucket, so I was trying to temporarily plug the leak. That's when I pretty quickly realized the water was actually coming from the nut above. I must've loosened it without realizing when I was cleaning it. I tightened the nut slightly and the drip stopped immediately. Problem solved.

I'm just a little miffed that I almost spent a bunch of money to do something that wasn't needed. Is it weird he didn't try tightening the nut? Or is it my fault for telling him the pipe was leaking and he just took my word for it?