I just don't understand why some people see them as any different.
Facebook has been far more careless and scandal prone, and it's business model (ads targeted to a person) requires a much more intimate invasion of privacy. Google may collect more private data, but its use is probably much more peripheral to its business (e.g. search term based ads can be pretty effectively targeted without an individual's profile). IMHO, Google's attempts to "improve" its products with private data has actually made them worse.
There are similarities though. Both companies have massive, concentrated influence over the information people see, and have the ability to make decisions that make all this Cambridge Analytica and fake news stuff look like child's play. There are also the economic distortions they both cause by having massively dominant market positions.