There is no reason to leave useless blank line in the end of file. At least it is very controversial rule and should not be part of standard.
there is no reason to leave useless blank line on the end of file
The core problem is what you define line and whether end-on-line character sequence is part of the line or not. UNIX-based editors (such as VIM) or tools (such as Git) use EOL character sequence as line terminator, therefore it's a part of the line. It's similar to use of semicolon (;) in C and Pascal. In C semicolon terminates statements, in Pascal it separates them.
"Blank line at the end of file" is ambiguous. The standard should define what is line of PHP source. I would recommend using UNIX-based definition (EOL character sequence as terminator).