They all pretty much say the same thing anyways.
That's a bad legal error to make on two counts:
1) All written material on a website (or really anywhere, be it a book, magazine, App, etc.) is copyrighted from the moment of creation. Read I have a question about copyright. What should I read before I ask it? You could be liable for copyright infringement if someone finds you have copied their work.
2) Privacy policies and terms of services for websites, businesses and governmental entities are more than likely drafted by lawyers, paid to cover all the bases in terms of privacy, liability and as such are legally water-tight (as much as possible) to protect both the entity and the user, like you. They are individually written for each entity because the legal devil is in the details of each service or business, and each and all liabilities must be addressed.
"...all pretty much say the same thing" isn't correct. They don't all say exactly the same thing. (Caveat: unless they're generated by a service, see below).
If you copy and paste, you run the risk of being liable for what you excluded or otherwise didn't consider in your policies, as those policies are now your legal documents, and are contracts for use of your service. See What is a contract and what is required for them to be valid? . (As well as being liable for copyright infringement).
Google will show you all kinds of services such as https://termsfeed.com/terms-service/generator/ These are useful for personal sites where your liability is nil and privacy is mostly moot if you don't collect data on visitors or allow them to contribute to the site. Such services require you to sign away liability to use their policies.
But if you're running a real business with real money and user content, you have real liability, so get a lawyer.