For the same reasons a pen aficionado appreciates and purchases a fine writing instrument when a pack of Pilots would do the job (you may have noticed that we have an entire subforum devoted to pens). That, and as others have mentioned, stainless steel will last forever with little or no maintenance.
I prefer the heft. If you like a lighter razor then stainless steel probably isn't for you.
. . . and they may be uncomfortably heavy.
I prefer the heft. If you like a lighter razor then stainless steel probably isn't for you.