imagine this then.
the glock 17 is cheaper to use than a 1911. but you know what, im going to dethrone the king. another classic option is the beretta 92. two rounds less but better sight. the glock's sights suck. youre gonna need a reflector or red dot. in order also to have a trigger pull that is pleasant as a 1911 or beretta 92 you would need aftermarket parts. thus the glock which is marginally cheaper becomes more expensive as you require more for better performance. a 1911 or 92 on the other hand has better sights and feels better. the latter of which has the bullet capacity you like. cheaper because they were made to be used standard. the choice sidearm for the us army. the glock is on the other hand used by criminals, police and austrian special forces. now, have you seen police surplus glocks? they have hella replacements and mods. an army surplus beretta 92 does not. so, in short, a "cheap" glock often could use modifications that depending on the quality push its price way higher than its competitors.