Is it dangerous to let multiple kids to stand up in the same shopping cart/trolley?

Your kid's shoes walk through tiny amounts of spit, puke and feces.  Please don't put it in the trolley that is used to carry food around a store.  Moron.

The trolley is there for your goods, not kids.  If you have a child yourself please ensure that the child is in the actual seat, not down inside the trolley.  Having more than one child in or on a trolley is asking for trouble and accidents.

it is quite dangerous

Yes, and a store employee may ask you to sit them down or remove them from the cart. It is dangerous.

it does sound dangerous, if you see that tell someone at the store about it

Idk you should try it, just to make sure it is safe

no as long as the weight is well distributed