Flash or no
 

Do you think it's rude to use the flash when taking pics at a nice restaurant

If it is something that will distract others from also enjoying their time then yes. And that's not just in a restaurant.

Yes, I do.

I vote yes. Increase your ISO and skip the flash

Invest on better lens, it´s better variant than increasing ISO

invest in what would have to be a larger/faster lens just to take photos of food at Arby's?? :) Especially when a decent camera can show ISO 3000 with little to no noise? Guess it depends on the camera.....

Smartphone or DSLR?

IMHO most cameras these days with stabilization do pretty well w/o flash. Unless you are bouncing flash or have a diffuser I find no-flash much more pleasing.

As to how distracting, if you only take one picture and know enough not to have to CHIMP, why not, no more distracting than all the other things that happen in restaurant. with lots of talking etc. etc. IMHO.

I think flashes can be distracting inside a restaurant. If you have a nice camera though, it's possible to just up the ISO and shoot without a flash.

No flash! I recently took photos in a fine dining establishment for my large party. I used flash on my camera phone because the lighting was rather dim and regretted it afterwards. Everyone's faces looked washed out. In the past I have turned off the flash and my camera phone has done a decent job. There are also some simple editing apps to improve the photos for sharing. FWIW I also thought I should try turning on the flash this time because the dining room was mostly empty except for out group and I took the photos facing a wall away from other diners.

If you taking a pic or two of your party as it is a special occasion then I think it is ok. However if you are taking pics of every meal or moment then yes it is annoying

Absolutely. Restaurants is one of those "especially" categories.

No Flash.

I do too. Also, I haven't used a flash indoors in a long time - modern digital cameras and even most phones have great low light capabilities.

you pull that stunt when i am dining, i will first create a scene, and if the restaurant does not throw you out, i will leave. i also think you should be banned from all nice restaurants. do you also leave your cell phone on and the ring tone plays something like the willam tell overture.