Austrian here. For the most part i agree, but i think there is more:
I am not really good at understanding how politics work, but i think having lots of smaller states with localized laws and different political parties (as in every state has their own parties, plus more than two) puts a bit of a dent into lobbying. This forces corporation to fight their wars via the customers instead of just buying a representative to write laws for them. Which is not to say there is no lobbying here (at the moment it's quite visible with big tobacco vs. vaping), but it seems to be less effective.
Also, europe being the younger collective means we are behind on lots of stuff. But we are quickly catching up: rights get diminished left and right, telcos now work across multiple countries, pseudo monopolies are on the rise. I am a customer with UPC, a multinational that bought our local cable provider Chello and local ADSL provider inode. Service quality and quality of the connection both have dropped significantly since then...
As for the citizens/customers: here in Austria we have multiple organisations that fight for consumer rights, and they do a pretty good job - i don't hear a lot about such things from america, so are there none or are they just powerless in america?