Chinese major banks prevents customers from buy gold, precious metals but WHY?

Major Chinese banks have taken measures to prevent customers from buying gold, platinum, palladium, and other precious metal-related products through them. The Shanghai Gold Exchange also says it may take necessary measures to curb gold trading to “protect investors.” Source

Some actions by the banks calls for questioning. Why would the banks bar customers from buying gold? The reason here is to curb the gold rush which is currently having gold peak at $1975 at the time of writing this post. I get curious when banks acts like this.
Why should customers be prevented from investing in precious metals at their own will and whenever?

The most common used word to bash Bitcoin is it volatility and so banks, media and governments keeps advising people to stay off Bitcoin and cryptocurrencies.
Preventing people from investing in gold with excuses such as protecting them to me is just an act of banks preventing people from moving their worthless fiats to safe havens.

Interestingly billions fake gold was as collateral to secure loans in China: Gold Industry Shaken as 83 Tons of Fake Gold Bars Used to Secure $2 Billion Loans in China
Do we really need banks? Do we need to be told what to invest in and what not?
Clearly this institution have no our interest at heart and just wants to keep holding on to the power of monopoly.

Further read: Link

Hopefully more people wake up and smell the foul being played.

We owe it to ourselves to make Hive great