When Hyflux issued her preference shares in 2011, OCBC was paying about 5.1% for their preference shares under OCBC (parent company) and OCBC Capital (Subsidiary). Hyflux paid 6% for the 2011 preference shares so it wasn't perceived as high-risk, back then the market interest rates were a little higher, it was fair-market value.
Then when Hyflux paid 6% for her 2016 perpetual bonds, again top banks including Julius Baer just issued 5.75% perpetual SGD bonds, even SP Power's AusNet Services (Electricity Asset) issued at 5.5% for their perpetuals. Again, it was just market rate. In fact, there was PIIGS crisis in Europe and UK and German banks such as HSBC were paying more than 6% and Deustsche Bank issued at 7.5%.
Therefore, I don't think we can consider Hyflux investors are gamblers or risk takers.