I cannot speak for the canadian market, as i do not live here, but in France we have quite a large choice, and were bottle rank from 5€ to 200€ in a good wine shop.
Assuming there is little return threshold on wine above $20 is, in my humble opinion, a mistake. Because you don't drink a price, but a work. And good work is never cheap.
I'm not talking about marketing, a wine harvested by a dwarf wrapped in ham on a full moon night before sorting the grape on the tights of virgins ... but about solid facts.
You might consider this :
Producer choices Above everything, a wine producer is a skilled craftman whom makes soil, cultivation, harvesting, ageing choices, to make the wine that fits his objectives. Whereas some may aim for low quality high quantity, a great number intend to make the best price over quality wine. And those choices can be expensive.
Weather It's plain stupid, but a wine is also a product of rains, snow, temperatures, insects, sickness ... production is random. Of course, you can add water, persticides, fertilizers, use UV light by night and cloudy days. But it'll not taste the same.
Soil&terroir Good soil is rare, and what is rare is expensive. Right terroir also is. Vine don't grow everywhere, and some places are better than other. And as those lands are rare ... Keep in mind that a century old vineyard and a ten years old one doesn't make the same grapes.
Breeding An industrial wine in steel cask doesn't age and develops flavor the same than in a concrete tank or wood barrel. A wine in a cellar doesn't age like one in estufagem. A wine draught too young will never be good. Don't forget that Pinot Noir, only vines allowed in Burgundy has to age two years in oak barrel and three years in bottle before being opened ? Or that a third of a Savagnin wine barrel evaporate in oxydation to get the taste right ? Well, the producer also has return treshold concerns ...
Harvesting If the harvest is machine made, it's cheap, but immature or rotten grapes go to the pressoir. If it's hand made, it's expensive, but the grapes (and sometimes, every single seed) are harvested the right day : not before, not after. And even after harvest, not everything proceeds to the pressoir.
Legal or crafting obligations In several places in Europe, traditions, rules, even laws determines quality standard. When only the upper two third of an harvest can be made into wine, and the worst third can only be transformed into other products, it has a cost. In France, you cannot put wood dust in your wine to flavour it woody. If you want the wood tastes, you get wood barrel. End of discussion. Adding sugar is restricted. You don't add brandy to cut fermentation. You don't add other fruits. In fact ... it must be 99.9% wine and 0.1% preservatives. If it needs something else than grapes, it's no wine. It's not a moral statement : it just simply isn't wine anymore.
Glass. Is your glass suited for the wine, and its degustation ? It's a common mistake, but there are three kind of glasses : 1/ degustation, standardized to test several wine in same objective conditions 2/ figured : you don't drink Pils, Stout, IPA and Weizenbock in the same beerglass do you ; It does also apply to wine, old&young, white&red does not required the same shape 3/ fancy bullshit. Sorry you bought them. And it's common in restaurant to have the wrong kind of glass.
Pairing Not every wine fits every dish. Not every wine fits every time of day. Not every wine meets your mood at a precise time.
Your tastes I'm rude, but do you know what you like ? I'm fond of oxydated wines. Most drinkers can't bear them. I don't enjoy champagne. Most drinkers swear by it. You might not have met what you like, and thus you might not know enough in oenology to assess nor appreciate the subtleties. It's easy to learn (if you have a good teacher), but it takes time. I do not buy expensive wines. Because i'm broke. And because i cannot enjoy them fully : i learn and wait until i'm able to enjoy them When i got my drivers licence, i drived a car older than i was. Today i can ride a common sports car. But i would not dare to drive a Porsche or a Ferrari : i would do nothing but find the nearest wall
I might expose twenty other factors that determines both price and quality.
There are great wines under 10€. Really ! Simple and straightforwards.
There are awful wines over 20€. Really ! Miscrafted, mishandled ...
So, please, step over your range boundaries. The threshold you wonder is several rung above the price's ladder ! Ask oenologists, do visit wine trade fair, try to meet producers ... or simply visit a true cellarman in his shop. It'll blow your tastebuds !
Source : my experience as beer cellarman for the importance of the crafting. And several hundred different wine bottle over the years.