Why do we need "eval"? (Expect question)

Consider this (Unix/Linux/bash) command line:

$ expect -- /dev/fd/3 3<<< 'eval spawn -noecho printf {{\t%s\n}} $argv;interact' $(seq 1 10)

This correctly generates the output (each line starts with a tab):

1
2
3
4
5
6
7
8
9
10

But notice how we have to use "eval" in order to split up the args in $argv.
And, since we are using "eval", we have to "double quote" (with {}) the
"format" arg to "printf".  It'd be nice if neither of these things were
necessary.

I've always believed that "eval" was "evil" and to be avoided if at all
possible - both in shell and in Tcl.  It has strange side effects, such as
we see here (the need to "double quote").  Is there any way to get the
above effect w/o using "eval" ?

--
"Every time Mitt opens his mouth, a swing state gets its wings."

(Should be on a bumper sticker)