BHG ID Attacking Corporations/Military/Police

[Sanctions]

The Guild even have their own capital ships. This all can not be done by individual bounty hunters which are in no way connected to each other.

If you are well-known and effective, any government would actually like to hire you and provide with any equipment you need (not in the terms of our own regulations, but in the terms of RP logic).

So why is the Bounty Hunters Guild lawful, and they would not seek out every kind of bounty out there? Well, because in vanilla, it was only the Houses that paid nicely and put out bounties on the scum of the space. The criminals surely would not be able to compete with a House when it comes to paying, and it is an easier and much happier job to work for the lawfuls, allowing you to be part of the civilization and enjoy everything being a lawful citizen of some House brings.

Right, but some serious empires like Maltesians/Hessians etc. as well as quasi-lawfuls and independent ones actually could compete with them. They are also "civilized" in their own ways, wealthy enough too.

That in my opinion is the root of things. It's not that the ex-criminal Hunters suddenly had a change of heart and wanted to be all goody goody vigilantes. They just saw the chance to become richer and more comfortable.
So the Guild started out as lawfuls and remained that way because they had already become rich, already had many assets in House space. It's not easy to work for the enemy later on, even if Discovery added some economy to the criminals.

When it's like 10 bounty hunters per 1 poor rogue whose ship is made of scrap, it's quite hard to imagine how they would get rich. And like governments would rely on them more than on military/police? Not sure.
Like some real PMCs, they could be used as a third-party dirt-cleaners, hired by "someone", presumably a government. That actually fits the RP logic, but it's prohibited, once again, by our own rules.