Artificial intelligence wireheading
The general thread of a number of artificial intelligence takeover stories (such as It Looks Like You're Trying to Take Over the World by the always-excellent Gwern) run along the following lines: 1. An agent is rewarded when something specific is achieved — for example, when a paperclip is produced....
I imagine there are regulations - intended for business as usual - that are interfering with people adapting to the new situation.
Inheritance tax and 'vacant house' charges distorting the market value of houses.
Possibly - anti-hunting laws that stop any willing person from hunting deer themselves.
With businesses that have dependent customers, where pressure is put on the aging owner to have a succession plan - what stops a PE firm rolling up all such companies in an industry, for a discount?