I have noticed that mp3 players around the 32Gb area seem to be fairly expensive; I haven't seen any for less than £150. Conversely, players with smaller storage can be found at a much lower price, for example 4Gb players are usually about £20.
32Gb MicroSD cards can be bought for around £12, so the price of storage does not appear to be the main factor.
If I were a cynic, I might think that companies are artificially inflating the prices of their higher-end models. However, I would like to know if there are any electrical or electronic limitations on creating cheap players with larger storage capacity. Perhaps there are problems with the battery life when using larger storage? Or difficulties with the ability to search the larger memory efficiently? Or is there a difference between MicroSD and the flash memory used in mp3 players?