They were not forced, it was their choice, and the choosen editor (vs6) do have search/replace. My personal guess is that keeping those BEGIN/END was seen as a smart move.
I guess they just liked the way it looked & felt? Really doesn't seem to make a difference to the development other than it feeling more familiar to Pascal devs.
It doesn't harm the development, indeed. However it does harm the developer's freedom in choosing his tools, for example Vim will try to fold regions delimited by brackets in C files. Nothing unbearable in the end.
