Originally Posted by
davidash
I most probably will remain with Marriott, but without a real incentive, it might drive me to become Elite at Starwood/etc.
I'd say one of your main benefits of lifetime Platinum is flexibility. Flexibility to stay at other hotel chains if you want, pursue their elite status as well, yet still know that you always have Marriott you can go to for the Platinum treatment. And from that perspective, it would certainly be in the best interest of Marriott to offer some sort of low level incentive that, when combined with the guaranteed Platinum, would keep you staying at their chain. Probably wouldn't take much... just something to keep you "in the hunt for the deal", and keep you away from the HH or GP or SPG.
If I were lifetime MR PLT, and I had 100+ nights the next year, I'd make sure I got Diamond HH and GP with the the first 60 nights, and would only stay at Marriott when convenient -- I have favorite hotels with each of Hilton, Hyatt, and Marriott and nirvana would be to be given the royal treatment at any of them when I am in town.