Like I said it’s cheap in the sense of bang for the buck. The ABV is slightly higher than a cheap wine. And the caffeine and other junk means it’ll get you more fucked up for your buck.
To my memory, at least in Ireland it skirted some of the alcohol taxes and had formerly been significantly cheaper.
Oddly enough that wasn’t the case by the time tabloid media decided it was worse than teens with knives.
Same element happens in the US. Natty Daddy might cost a dollar more that Colt 45. But the Natty has a much higher ABV. So it’s a cheaper way to get drunk in the end. As a result Natty Daddy is the top selling value malt liquor product in the US.