To put cost of blanks into perspective, the Americans can have a Lothar Walther barrel machined and fitted to their gun for around $120, that's £75, for a one-off custom job. Now if the smooth twist barrel blank is twice as much as the Lothar, it should hardly make a huge difference to the total cost of a gun.
There's maybe a good grain of truth in Hares Ear's earlier post.
If it's more expensive, it must be better, even if there's no commercial need for it to be more expensive.
Flavour of the month works in most hobbies
Walther CP-2 Match, FAS 604 & Tau 7 target pistols, Smith & Wesson 6" & 4" co2 pistol, Crosman 1377,
Baikal IZH 53 pistol, Gamo CFX Royal,177, Umarex SA-10 CO2 pistol.