I noticed lately - over the last year, anyhow - in many cafes in the Marais, tables are being set for meals much earlier than they used to be. I wonder if this is happening much in other parts of Paris, or just mainly in the areas where tourists are demanding to eat earlier than traditional meal times.
Patrons used to be allowed to sit anywhere, just for drinks and perhaps a dessert or light snack, between the approximate hours of 11 AM - 1 PM, then again from 3 PM - 7:30 PM. But in my neck of the woods, tables are being set all day long, and you must ask if it's possible to just sit for a drink - some places grudgingly remove the place settings, others are nice about it. Several places near my apartment start setting the tables at 6 AM, even when they don't serve anything until 7:30AM - or in a couple of other cases, at noon!
I'm sure it's the economy,and I'm sure tourists appreciate it, but it certainly isn't traditional, and it can be definitely annoying. I really hate to see one of the Parisian culture's finest traditions being swept away, just so someone can make a buck.
So, if you arrive outside of the traditional meal times I mentioned and see all the tables set, go ahead and ask. All anyone can say is "no" - but they won't see me, again.