Some chain restaurants are fine, it depends on your tastes. I'm not a food snob, I like pub grub here in the UK and I like diner food in the US. Soup & bread is my favorite and I can find that in lots of eateries. What I miss is a plate of hotcakes/pancakes or fat french toast. I'll have some the next time I'm back home.
I'm not a food snob either, I work on the rule of the right food for the right occasion, so a mid week dinner, or a random lunch would not be on the same level as a Saturday night out or special occasion.
Chains for me have their place in certain situations, lunches, when in unfamiliar towns or travelling, mid-week, they often offer good value and a "safe" experience, you know what you're going to get and that's reassuring. I wouldn't outlaw chains by any means
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I also think they offer a lot to families on tight budgets, especially as they often offer 50% off or 2 for 1.
Where I think there's an issue is when they're a first choice over local or better restaurants, like I have no idea why people in London visit chain restaurants for nights out when they live near to amazing places, but I would have a different opinion if I lived somewhere smaller without the choices you get in bigger cities.
I just hate seeing Pizza Express packed out when you could be at
http://www.santamariapizzeria.com/ or
http://francomanca.co.uk/, but if it was my only option, I'd be happy to go because it's a known quantity (except I'm boycotting Pizza Express because I've tried to have lunch there twice in recent years and they've been so terrible both times to the point of having to walk out) but again, I'm lucky because those restaurants are near me.
I would love to have somewhere like this open up around here -
http://www.southcongresscafe.com/menu-brunch.phpTheir carrot cake french toast was to die for!