I'm not so sure it's just a US thing. I've been to plenty of places in EU that are very interested in feeding you and getting you out the door for the next peop

I'm not so sure it's just a US thing. I've been to plenty of places in EU that are very interested in feeding you and getting you out the door for the next people to come in. Some high end, in-demand places will even tell you up front what the time limit is because with their limited space, they need to be able to accommodate the next reservation. And often, it just comes down to overcorrection, where the server is afraid of getting bad tips (so yes, that is US specific, and maybe related to throughput, though not exclusively), or incompetency, where they haven't learned how to read the table and predict their needs.