I didn't like the Alice books because I found them creepy and horribly unfunny in a nasty, plonking, Victorian way. Oh, here's Mr. Christmas Pudding On Legs, hohohoho, here's a Caterpillar Smoking A Pipe, hohohoho. When I was a kid the books created in me about the same revulsion as you get when, aged seven, you're invited to kiss your great-grandmother.
The above quote summarizes Terry Pratchett's feelings about Lewis Carroll. Hard to argue with him, but he's sniffed out the main reason I like Carroll. There's something sinister beneath all the quirky Victorian wordplay, and I really liked how he balanced that out. The Mad Hatter's tea party is goofy, but the Hatter is so chaotic (meaning alternately silly and deadly serious about his Rules) that I feel like he could snap and kick the table over at any moment. Which isn't a new observation or anything, but the first Alice book has a very malicious subtext throughout that I really like. It's amazing how well he balanced that with the frivolity of the narrative voice for so long.
So, uh, yeah. Take THAT, Terry Pratchett.