I believe the pressing need is suppressed by the very fact that it is illegal and therefore free speech on the subject is suppressed. Whenever you see media stories about its use and people speaking up usually for medical use then sooner or later they will be arrested for home grown or similar, this discourages open and free speech on the subject.
Ordinary people put pressure on politicians and politicians have to act, call it lobbying, it works for industries that want to change regulations and regimes, this one is led by ordinary people. There is some industry backing for legalisation in this country (Richard Branson is an outspoken user and advocate who I'm sure is ready to invest in an industry worth billions).
But ultimately it is ordinary people that want it.