Which is why they determined Google's market dominance in Search, not shopping sites.
Your analogy should be about the single most popular restaurant guide in town, opening up their own restaurant and then only writing reviews for that.
The quality of Google's in-house shopping business didn't factor into the EU Commission's rulings at all. Which makes a lot of sense because, given Google's market dominance in Search, it is impossible to know if their shopping business is in fact superior or not, because they abused that power (gained from Search, not building a superior shopping business) to stifle any competition.
As the article clearly states, market dominance is not illegal (like your restaurant analogy suggests), irresponsibly abusing the power that comes with it is.
Nope. It's crazy. You don't go to the most popular restaurant in town and have them tell you to go get desert across the street because the superior food and experience hurt their sales.
Even looking at the commissions fact sheet (Search Engine market share) [0]. 3 of the 4 other companies are billion dollar enterprises. Microsoft decided to make it difficult to switch to Chrome/Google in Windows 10 (no more 1 click). With this consumers are still switching back.
Out of all the bad shit google does, this shouldn't even be on the radar.
For the other end of the story this is an interesting read [1].
[0] - http://europa.eu/rapid/press-release_MEMO-17-1785_en.htm [1] - http://www.foundem.co.uk/Foundem_Google_Timeline.pdf