P2P (aka BMK / benzl methyl ketone) can be used to make either amphetamines or methamphetamines, I think the only difference is that the chemist would use methylamine instead of ethylamine in the reaction to get meth, along with whatever reducing agent is used.
Now P2P, methylamine and ethylamine are all substances that have legitimate uses in industry and production of pharmaceuticals etc, so they are commerically available but are closely watched. All chemical supply companies have to adhere to strict reporting requirements for any suspicious purchase of wacthed chemicals. So, if you were to set up a ficticous company, rent out a premise, make an account with Sigma-Aldrich, then order 1kg of P2P, you wouldnt receive your order, rather you'd have an early morning wake up call with SOCA officers kicking your door down. (or the DEA in the States).
So small lab clandestine chemists do use pseudo-ephedrine because its relatively OTC in pharmaceutical products (although again it is a watched chemical itself so cant be ordered from a chemical supply company).
Big labs run by organised gangs have the resources to "divert" things like P2P, whether it be stealing it from legitimate labs or smuggling it from China etc.