Give a guy a license to print money
And he'd run the printers at full speed wouldn't he ? That's what a patent granting office has, in the sense each patent is a monopoly and collects application fees, more of which are likely to be paid the more likely it is for a patent application to be granted.
Low quality patents are a cost for everyone else. You run a small business, which a large business says treads on an obvious patent ? You can't afford the few million in legal fees to have it questioned ? Your business now has to pay tribute, or goes bust or can only afford to continue if taken over. If you pay for a product or service which requires patent licenses it's going to cost you more and we all pay more for such products and services.