Not only that, Android applications respond to event like "you are about to be killed, please serialize your state" or "please restore your state", something that "classic" linux applications do not support.
Android is not typical linux - it is not supposed to run on devices with gigabytes of fast memory running off AC outlet. When your memory bandwith is two orders of magnite lower, you have 128MB of it (on G1, 64MB of memory is used by the radio) and you are on battery, putting GNU system there would be not very smart - if you want something usable and with battery life longer than few hours, that is.
Android is not typical linux - it is not supposed to run on devices with gigabytes of fast memory running off AC outlet. When your memory bandwith is two orders of magnite lower, you have 128MB of it (on G1, 64MB of memory is used by the radio) and you are on battery, putting GNU system there would be not very smart - if you want something usable and with battery life longer than few hours, that is.