It is the kind of difference between two comics that hits you right in the wallet, because the initial cost of the cover price variant was different from the cost of the regular copy. That's a difference which is very easy for people to grasp.
When you have two different comics and all that physically varies between them is the cover price box, "Cover Price Variant" is a natural and easy concept. It is also a difference that is very easy to spot, even for a novice collector (can you spot the higher cover price variant in each of the pairs at right? Of course you can!).
Our hobby has a long history of embracing cover price variants as sought-after collectibles.
Two of the most well-known "categories" of highly-collectible cover price variant comics are "Type 1 Price Variants" and "Type 1A Price Variants" as defined below:
Examples of Type 1 cover price variant comics include 30¢ variants and 35¢ variants from the 1970's. These had a distribution area restricted to certain "test market" areas.
X-Men #100, 30¢ Cover Price Variant (Marvel Comics)
Star Wars #1, 35¢ Cover Price Variant (Marvel Comics)
Examples of Type 1A cover price variants include 75¢ variants and 95¢ variants from the 1980's. These had a distribution area restricted to Canadian newsstands.
Archie's Girls Betty and Veronica #320 75¢ Cover Price Variant (Archie Comics)
Batman #366 95¢ Cover Price Variant (DC Comics)
With their distribution "naturally" restricted (not artificially restricted like some modern day 1:whatever retailer incentive variants), Type 1/1A cover price variant comics have a natural appeal given their clear rarity characteristics. Although Canadian Price Variants may be the most well-followed of the Type 1A family of price variants (and the subject of the Canadian Price Variant Comics Price Guide), there are actually two other classes of Type 1A price variants as well: Australian Price Variants and U.K. Price Variants.
In these cases, instead of the cover price variant having a distribution "area" defined geographically (like with the Type 1 variants being restricted to test markets and Type 1A variants being restricted to a particular country like Canada), the cover price variant was restricted by distribution channel, being available only through the newsstand distribution channel (if the difference between newsstand and direct edition comics is new to you, see this introductory article: Comic Book Newsstand Editions: Understanding The Difference).
Venom/Deadpool: What If? #1 $3.99 Cover Price Variant (Marvel Comics)