To be fair that is a lot of professions: lawyers, accountants, doctors, dentists, car mechanics. All could advise you need a service you don’t really need but maximises their revenue.

Except a decent number of those examples have legally binding oaths not to screw you. And if they are found to have screwed you, are barred from their profession and have to pay you a lot of money. Maybe that should be more common.

Car mechanics and dentists do that all the time. I have not much experience with others.