This is true, but - and maybe this doesn't matter to some people, but it does to me - it's a MUCH nicer walk through Downtown Disney. Especially in the evening, when there is lots of live music - DTD has a great vibe. I have only stayed at the Grand, not the DLH, but don't mind walking over to the DLH for dinner at Goofy's . . . plus it's not far from the monorail which takes you directly into Tomorrowland.
To me, aside from the proximity and feeling like you're on a Disney vacation, the perks are really worth it if you are going during peak season. Beginning of October, maybe not as worthwhile. We go in the summer and the extra hour in DCA and, this summer, the extra FPs were huge! You also get the MMs though we have yet to use them - it's nice to have the option!
I think you can have a great time no matter what, but there is a little extra Disney magic if you stay on site!