Probably wayyy lower.

Obviously I can only speak for my immediate area; I myself live in The Netherlands in a city of about 650k, and there are just two stores in the entire city of the chain I mentioned earlier. Used to be three, but I guess one wasn’t having enough customers. Then, broadening the scope a bit, the immediate urban area of all adjacent towns has a population of over a million, 1.1m maybe 1.2m, but there’s still only two more stores. So I guess that’s one store for like 250-300k people. Toy stores sell games as well, and there are a lot of those, and so does Media Mart, a big electronics store, but they all only sell new.

This is the opposite of me. I almost never buy used games, and I oftentimes buy games when they first come out. Mostly because of hype, as I get excited to play games long before they come out, so although some might say that waiting a couple months isn't a big deal, I've oftentimes already waited several months, or longer.

I own many games that I haven't actually played yet.

I haven't always been this way, but in recent years I've began getting disposable income and that has resulted in a dramatic increase in my spending habits

Yeah, that sounds like a lot less.  (Again we are only comparing my city to yours, so this is just anecdotal at this point.)  I also was only counting used game stores.  Every Walmart, Target, and Best Buy also sell new games here.  Walmarts are all over the place.  Toys R Us used to sell new games also, but they just went out of business due to poor management.

keep in mind that plenty of europeans (myself included) do prefer to buy digital games on the US marketplace on conversion rate alone. 60$ does not equal 60€, so for me it was a no brainer to keep a US PSN account as my main

We americans get bored quicker.