To actually answer the OP's question... The Wouxun KG-UV2D/KG-UVD1P series dual band handhelds, available on ebay/wouxun.us/elsewhere, have a roger tone feature (because of their commercial background).
That said, I agree that it is generally not necessary or appreciated for ham use. I think for commercial operations, it is common that people have their radio strapped on, but aren't actively listening - if they need to bust in with a quick transmission, the beep helps confirm to them that the transmission is over. Hams are usually paying attention at the time they want to make a transmission.
If a repeater operator wants to implement something due to the time the repeater takes to quiet or unkey, they can do that at their discretion - the radio operators don't need to individually implement it.
-Sam