Well, the most likely reason is you don't think Morse is a good bet long term after his current deal is up.
When a guy strikes out a lot, but doesn't walk... that usually catches up to most hitters in their early 30's... they're kind of like a ticking time bomb. Some guys last to late 40's, some guys fizzle out quick.
Makes sense- and thankfully we have 3 rookies in OF that I know of (Harper, Moore and Brown) who seem to AT LEAST be capable in that position. Out with the old, in with the new, huh?