With RAM, you normally mean two things.

1) That you can access the memory cells in any order.

2) That you have symmetrical read and write speeds.

But many modern memory technologies have quite varying memory access times. You can access data within a page way faster than what it takes when switching between pages.

Since you have memory pages, the access is not really random access - the chip behaves differently depending on if your previous access was within the page or not.

Burst accesses aren't just because of internal processor caches. It is also a question of transmitting as much data as possible with as few signal changes as possible to keep down the number of signal lines or the frequency needed or both (and to keep down the amount of power to toggle the signals). With true random access, every single memory access must supply a full address and that is very expensive with todays high memory bandwidth requirements. A slow PC memory stick manages quite a number of CDs per second...