Let me toss in another vote FOR a kickstand, with a couple caveats.
Why? As John mentioned, it's easier to load/unload/find stuff in your pannier with a free-standing bike. IME, it's also more stable than leaning the bike up against a wall, post, fence, etc. My main bike no longer has a kickstand (replacement frame doesn't have room for both a kickstand and rear fender). It's an art to lean the bike against something, let the front wheel flop, adjust the angle of the bike, step back with fingers crossed, and then jump back to catch the bike as it finds a way to roll 6" and fall down, scratching the paint all the way. I've also seen too many nice bikes on larger rides fall on the derailer, bending the hanger and making shifting difficult for the remainder of the ride.
John's golf ball recommendation is spot on. No worries about impaling someone or punching a hole in soft turf, leading to the bike falling. FWIW, I like the kickstand that mounts on the rear triangle.
Caveats? With the rear kickstand (somewhat less on the center mount), a loaded bike will find downhill, if there is one, and swing around until the front is pointed that way. It may then start to roll off the kickstand, depending on the front wheel's angle, and down goes the bike. I've seen the same thing happen in gusty winds. Sometimes it's best just to lay the bike down on its panniers.
