My plumber charges me about 90 Euros per hour. He told me that this was because the apprenticeship to become a plumber was much longer at around 6 years.
This is expensive, even for a plumber.
Problem is you can't outsourcing plumbing in China or other low-wage countries. It has to be local. And you need your plumber, there is no alternative. So he sets the price.
To come back to our line of work, I know many tailors who do only alterations, no bespoke. This is because they earn more from alterations : people need them, and want them in their vicinity. And they don't make difficult and time-consuming alterations, just hems and this kind of thing. Making hems all day, you can earn 50 per hour, sometimes more. And of course, they don't make hems in a time consuming way, they keep them simple, quick done. Some even just fuse the hem, no sewing. And they charge more if you want a heel stay. It is impossible to earn 60 per hour if you make coats. Actually, it is at least twice what you earn making coats.