because there's not mushroom inside

The UK has just reclassified magic mushrooms as Class A Drugs (note the capital D).
BBC News

I can't wait to see the Columbians rip out all of their coca crops and replace them with humidity controlled fungus sheds.
I realise that a few people who are susceptible to schizophrenia may be adversely affected, but it's not like the other 99.5% of shroomers are ruining their lives. The only reason that psychedelic drugs are illegal is because governments know that their mental health care systems are not up to scratch. Mushrooms may help bring on people's psychological problems, but at least it gets it out in the open instead of leaving their mental illness to fester untreated.

Also, making stuff illegal only makes it more attractive to young people. The same people that the law is looking to protect. I'm not saying to scrap the law, but just realise that a lot of people are going to try drugs at some point and there's no sense in making them deal with criminals to get them.

Verdict: Standard government knee jerk reaction to a crying parent