What is allowed and isn't allowed really varies depending on where you are. There are plenty of places where fires without a ring are allowed (much of crown land below the alpine level) and plenty of places where you could have an illegal fire and never get caught. That said these regulations have been brought in for a reason. I am pretty sure fires are never allowed in Garibaldi park (of course anywhere around whistler = touristy anyways). Manning Park campgrounds allow fires in rings but these campgrounds get BUSY.
IMO your better bet if you want an actual campground would be something around the Pemberton/Lillooet area because the further you drive the less people there will be. There are some really nice campsites that have logging roads for access and as a result won't be too touristy. Pretty well any designated car accessible campground will have fire pits. I've only stayed at Kingdom Lake Campground because I generally stick to backpacking. It is a beautiful spot, and was great until a pack of Bralorne locals showed up complete with massive trucks and speakers. Look at Gun Lake Campground, I've never been there but it's pretty small and is owned by BC Hydro (they are generally pretty well maintained). Birkenhead lake has a campground, I think it's a fair bit larger. If you want to go the find a random spot at the end of a logging road route this is also a good place to start... you can pretty much drive anywhere. I'm sorry I can't help too much because most of my time is spent in the alpine where fires are never allowed.
Also, for large parts of the summer in recent years there has been a blanket ban on backcountry fires and at times on any sort of campfire anywhere because of the wildfires. They've actually had to close off access entirely to some of these areas. You need to check for these right before you go and do not mess any bans. Use this link to check for current bans
http://bcwildfire.ca/hprScripts/WildfireNews/Bans.asp
Here is some stuff copied from the BC Parks webpage, that has the guidelines for fires without a pit if you decide that's the way you want to go:Where campfires are permitted, and approved fire-rings or pits are not available, follow these guidelines when building your campfire

repare your campfire by removing all leaves, twigs and other flammable material from an area extending at least 30 centimetres around the fire.Be sure to scrape or dig down to mineral soil.Build your campfires at least three metres from any log, stump, snag, standing tree or wooden structureThe size of the campfire must not exceed one metre in height and one metre in diameter; the best cooking fires are small and hot.Equip yourself with a shovel or a pail of water containing at least 8 litres and keep near the fire at all times.Attend your campfire at all times and be certain it is extinguished before leaving it. Sift the ashes with your fingers to be sure. *I added this myself* Do not take any live wood to build the fire. There is plenty of deadfall. Lots of people are very against backcountry fires in general, I see no harm as long as there is no damage to the surroundings [/list]