Are we going to repeat the system where Blockcredits custodians will try to elevate grants to start operating in small and untrustworthy exchanges and the Shareholders will cover the losses after the unavoidables hacks/adminrunnings?
BlockShares holders will have full control over which exchanges its custodians sell on since there is no centralized control by its developers. This means that shareholders could conceivably only elect BKC custodians that operate directly on B&C Exchange's safe platform.
It is also worth pointing out that "mutualizing all the losses that custodians are going to suffer" is outside the scope of B&C Exchange operations because BlockCredits will not be supported at any specific price level. They will simply be sold for 1.00 USD. In the event that BKC are stolen from a custodian operating on a centralized exchange, they would likely be dumped on other exchanges for fractions of a dollar. Shareholders would only suffer lost revenue from the lack of new BKC being sold during the time the stolen BKC were dumped. For this reason, it is also likely that shareholders will prefer granting small batches of BKC to a custodian that will last for a week or two, rather than providing a year-long supply of BKC up front. Continuous replenishment of BKC to custodians is very easy in our design.
The design of B&C Exchange will protect networks like NuBits from the unpredictable and devastating failings of centralized exchanges. You are right that NuShareholders have not recently voted to give themselves a dividend as they work to recover from the exchange hackings of February. The dividend mechanism has been used in the past however and is fully functional.