Yes, but tiresome when you have 100 great images all with slightly different white balances. A white balance aid would help keep things consistent.

I don't often have a 100 great images! :D

always better to try get the WB right or near as can at capture. Correcting later can really screw up things like noise and exposure which is even more tricky to fix.
You have 2000 images to sift through after a game, you'll not want to get bogged down spending an age working out whether an image might look good once you spent 30 minutes Pshop work on it!.......maybe after all the playing you might just make the following weekend game?!

I have never read anywhere that if you shoot in RAW that altering the white balance will affect the picture quality. Anyway, if I shot a match then I would look at the photos more for content than absolutely accurate white balance. On a typical grey overcast day the setting cloudy will not be a million miles out! The exact colour balance will shift as the full 90 minutes progresses anyway, possibly from moment to moment, there is no way that you could keep checking the W/B. The goal would happen at the wrong moment and you would miss it! Surely the use of the expo disc or similar is for the considered shot in tricky lighting condition, say mixed natural/artificial lighting like an interior lit by tungsten or strip lighting and daylight. That could be very useful to give a correct reading but for maximum quality you would still shoot in RAW and maybe change the W/B off the correct setting to give the atmosphere you want. Don't get me wrong, I agree that in general terms it is better to get things right in camera but the expo disc is only a guide and starting point and not necessarily a good idea for fast moving action, in shade one second bright sunshine the next!

You're making big assumptions that we're outside, and that we're shooting a 90minute match (football?)!:confused:
so,
Manually set your white balance to sunny conditions. Take a picture under household bulb light. 'correct' that white balance.
Now take the same picture with a correct WB setting in camera at the time of shooting....
so tell me you're getting exactly the same quality in both shots, and you didn't need to crank up the exposure slider in P'shop whilst correcting your first shot?

come off it Mike...lol.......this is a wind up just for the sake of it, isn't it?! ;):D

S'funny, I thought your post was just a wind up too! :D Quite a few assumptions were made by you too which is why I LOL too when I read your post. :)