I'm of the opinion that whining about comp in a no comp tournament is inherently unsportsmanlike and deserving of a bad sports score, particularly if the person is using comp as an outlet for expressing what a sore loser they are.

Now normally my sports scoring is all or nothing. If you don't cheat and are polite, you get full points from me. If not, you get a zero and I tell you I gave you a zero (happened to do this at the last tournament I went to).

So should I be zeroing people that whine about my army during and after the game? (assuming it's a no comp tournament?) Should I bend on the all or nothing and just give them one tick from zero?

Yes

should you have to put up with someone whining about cheese?

No

...normally my sports scoring is...

Here lies the problem, everyone has a different algorithm, it's not objective.  Whatever the criteria, the problem lies in the scoring system.  Comp/Sportsmanship is inhernetly flawed, that's what a judge is for, to judge.  There should not be an arbitrary factor in an award like overall. Eliminate it.  A restructuring solves all of this.  Predicated on a decent FAQ, a published scoring system,  the elimination of comp, and judges who actually make consistent rulings; the awards should be:

Best General: Based on VPs

Best Painted: Judges Choice

People's Choice: Popular vote

Possibly with places 1-3 for each.  Best sportsman, a noble concept, but an utter failure, is completely meaningless because "theme" and "niceness", are abstract concepts that defy metrics.

I suggest a tourney player in any kind of comp system make the devils deal:

Mark each other perfect comp and sportsman before the game flavors anything and get on with the tournament.

Sportsmanship has its issues, but the overall assessment I get from everyone who attended GTs prior to it, is that there was a much higher percentage of out and out jerks in attendance. 

The existence of Sports scoring, and in particular the fact that it figures into the Overall scoring, forces people to at least make an effort to be a nice guy.  Most folks will anyway, but in any competitive arena, you need some mechanism to rein in the overcompetitive bell ends.

The fact that Sportsmanship scoring is subjective doesn't make it useless.  At least some fraction of painting scoring is also subjective, but we're not tossing it out- common opinion holds that tournaments are better events if everyone is painted, and people make an effort.  If the scoring requires painting if you want to do well, even the guys who don't give a toss for painting have an incentive to make an effort.

I've seen several different metrics for Sports scoring, and while the 1-5 scale is a long way from perfect, with good descriptions for each level it works decently.  People who ignore it, or themselves ruin its validity by being bad sports themselves, are not a reasonable excuse for tossing the whole thing.   Two wrongs don't make a right.

Anyway, it is possible to design a better system, too.  I've come up with one and used it at two tournaments so far to generally good reviews.  If we criticise GW for lazy game design, it's a bit hypocritical for us not to put a little effort into good tournament design if we're running events.