Montreal would give me pause if I couldn't argue the toss in French. I've had some excellent service there but also the rudest service, called names (in French that they assumed I didn't understand!) and actually shouted at for 'not' leaving a tip - my father doesn't believe in tipping, my mother and I do as in Rome (and I live in Canada so hardly new to me) so when my father pays by card, either my mother and I discreetly (by prior ladies room visit to see who has what cash!) leave a 'correct' cash tip tucked under a water glass or similar (we even offer to 'check' the bill for my father as his sight isn't great to make sure we don't unintentionally stiff them!!!

In all my years, in all the world, never has a waiter shouted at us when the slip has read a low amount - a couple have asked whether the service was ok (and my mother and I have our routine down pat for that so everyone is happy!) but this guy in Montreal was obnoxious and I made a point of picking the cash up off the table (he hadn't noticed) and pointedly putting it in my purse while telling him why in (albeit poor!) French! I mention this because this restaurant is on opentable, and I cannot see them giving change with servers like that!!!

I have no issue with concierges using opentable but I'd also expect them to be able to call the restaurant directly to get a table if space wasn't showing free, and I don't know that a concierge would have that pull if they didn't have a direct relationship with the restaurant. I know half a dozen restaurants where I can normally secure an otherwise sold out table because I am known to them, know them by name and sight, etc. and I don't think that would happen if I didn't have a personal relationship with them / their cell phone numbers etc.