My wife and I take turns each night doing bedtime for our two girls, 4/6. I have the full C&H box set and, a whiiiiile back, my oldest asked what it was and if we could read it.

For over a year now, any time it's my time to do bedtime, we have to read C&H and cannot read anything else. We've been cruising through it from start to finish and are, within the next week or so, going to reach the end.

Both kiddos, especially my oldest, have been demanding that we start it over. I'll probably table it for a couple of years and then come back to it when they're just a bit older, but yeah... kids definitely know about it and really do appreciate/enjoy it.

Edit: To say nothing of the idea that, eventually, everything fades into obscurity. I feel like what you're lamenting is something that actually jives with Watterson philosophically.