The EU is totally bonkers!!! And these fines are largely uncalled for. It's their site; why shouldn't a business up-sell to their customers? I know plenty of people who do it all the time. That's part of the point of being in business. If a user doesn't want to buy from Google, simply don't click the buy button.
Google search is the door to the internet for a majority of the world population. And then they had the brilliant idea to give their own services prime real estate on this door, thereby completely screwing alternative providers out of the traffic.
It is when you involve the state in creating a monopoly that you have problems. Consumers continue to patronize a business to the point of it being a monopoly because it serves them well. In a free market environment, this cannot be a bad thing.
Is it much more related to the fact they already have a quasi monopoly on one domain, and they leverage it to acquire more power or market share in another area.