Death is one reason to avoid excessive wallet balances. Traditional mobile contracts typically waive early termination fees when the subscriber dies. Mobile carriers such as SIMBA and Eight that allow hefty wallet balances apparently don't provide wallet refunds (or at least wallet balance transfers) to survivors. That's a problem in my view, and I think the regulator ought to take action here — for example, to limit nonrefundable wallet balances to S$120 (equivalent to S$10 per month for 12 months).
I think $500 is a more practical limit, especially considered the real value may be $250 instead. Moreover, $250 lost is quite small compared to many items overlooked by beneficiary like old bank acc, insurance policies, shares, hidden treasure box, etc by the decease.
And frankly speaking, if you ask those who have accumulated lots of credits in their mobile account wallet will they mind if it is forfeited upon death. They will not mind, they are buying peace of mind. If death falls upon, who cares about this anymore? It is the surviving members that are complaining.