Yeah there are plenty of companies that don't do code reviews still to this day. I worked for an ad agency for a bit and we were still using SVN (afaik they are still using SVN for many projects today). Everyone would just push code straight to trunk with no review process.

I created a cool little easer egg where if you clicked in the bottom left corner of the browser window and dragged in a circle, the site would flip upside down. A coworker and I also photoshopped some of the client's imagery that was used on the site and hosted it on another domain. If you typed a variation of the Konami code while on the site, the images would be replaced with our meme-ified versions of their imagery. Even if we had a code review process, none of my coworkers would have even noticed that little bit of extra code in the mess of jQuery spaghetti that was their codebase.