You see, LB was 20 times bigger than DBS. You put your money in DBS because you believe it is safe. With something well-known and 20 times bigger surely it is more safe.
If at that time someone told you 'save, no risks', it is logical, right?
Some people might have thought this way too, so they invested.
Just heard the news that some town councils also bought LB-linked investments. See, they also thought it was safe.