My long time Indonesian collegue and friend told me in Indonesian
reduplicatives are used to express 'many' . Like f.i. gado gado is a vegetable dish which consists of many "tauge" (soybean sprouts) and "tahu" (tofu) + peanut sauce and spices + egg. It is used for plural things.
(sorry I can't bring up more examples directly)

Maybe there are more languages that have this speciality.

It's fairly common. Nuncle could be more specific.

Baahasa Malaysia, like Indonesian, a closely-related language, expresses plurality through re-duplication. For example, the Men's room is 'Laki-Laki', to stroll aimlessly is 'Jalan-Jalan' and so on.

Google reduplication and you'll get plenty of information on the process. Here's an example.

Most of the ground has been covered. Reduplication is a kind of phono-aesthetic phonological process that can be used for different morphological reasons: augmentation, diminuation, number (plurals), tense (perfects in PIE, Greek, and Latin), jocularity, melioration, pejoration, etc.

As for Pinker's explanation for razzle-dazzle, I say Pinker-shminker. There the stop comes first.

Thanks ! Good link! Memories comes back now. Alang alang means grass.