360 owners wouldn't have to purposely RROD their systems near the end of the warranty period if the consoles were reliable. I hardly think that 3 years is an unreasonable time frame for a piece of hardware to live. The reason they do it is out of fear that it goes past the 3 year warranty period, then dies, leaving the owner with a repair bill.
It's perfectly feasible to RROD it near the end of the warranty. It's not as if the majority of Xbox owners don't fork out £40 for new releases and £40 a year to use Xbox live, I think they pay enough, I don't see why they should pay again for a piece of hardware that still has technical issues that aren't the end users fault.