Re: this probably sounds stupid.
Original anon,
As with so many things, it comes down to money. You can avoid the laws and taxes of a country by claiming to be entirely abroad. And that might work when you are. Although in your Google satellite example, the EU could simply jam their comms. At some point the internet enters or leaves the legal jurisdiction and can be interfered with there.
But that's often too much hassle. So the other thing to interfere with is finance. After all, Google make almost all their money from advertising. Google are now an illegal operation / terrorists / enemies of the state / being annoying / delete as applicable... In which case we simply make it illegal for you to advertise on Google. They lose their cash, what's the point of operating in the EU.
This is the way the US chose to fight online gambling. They couldn't make foreign sites illegal, but they could make it illegal for their citizens to partake. And they could make it illegal for their banks and credit card companies to facilitate transactions related to it. I'm sure it didn't stop people doing it, but it made it much harder.
Similarly the US Treasury Department believe they can cripple the Russian economy with sanctions, without any help from the EU governments. Because the US government can tell its banks not to deal with the Russian ones, and also any bank that wants to operate in the US. Thus they can make it extremely awkward for any global bank to have dealings with any Russian bank they sanction. They picked a small one that had close links to Putin's inner circle and Gazprom - and I rather suspect that this shot across the bows was one of the reasons Putin backed off a bit on Ukraine.
International sanctions on Iran have proved this to be at least somewhat effective. UN sanctions have had quite a bit effect, but it seems to be generally believed that pressure on Iranian access to international banking has also been very significant (although I understand that a lot of that was in cooperation with the EU).