It's not about lawyers cutting a good deal for themselves. Liability issues get complicated along multiple dimensions when they involve licensed professionals, even when they're day-to-day working relationship is indistinguishable from any other employee. And lawyers, even more than doctors, are at the furthest extreme of this complication spectrum. Even were software engineering to become a mandatorily licensed profession like some other engineering disciplines, there's little reason to believe insurance products would mirror those in the legal profession. I seriously doubt we'd end up in a place where employers are common--let alone routinely--paying to cover liability for work outside the scope of employment.

It's because it's simpler to insure "everything real estate" or whatever than to try to cut out exclusions for (relatively) cheap properties.

But if they noticed that they were paying out more than expected on these $500k deals, the insurance would change quite quickly.

The same thing happened with GA insurance - there was an assumption that airline pilots would be safer but it didn't really turn out as expected, because a 747 has a heck of a lot more "keep you safe" doohickeys and doesn't fly low to the ground much.