Well, it's not like this is something new. Companies have been able to trademark colors for some time. And it's not like Fluke is some unknown company -- they've been around for a long time and everyone in the industry knows their multimeters are yellow around the edges. I'm skeptical that Sparkfun is completely innocent in all this. A quick look at their website shows that their company colors feature red, which appears to even apply to their circuit boards and tools. One would think their multimeters would be red, not yellow.
And as for forcing them to be destroyed, well that's how customs has always worked. Thirty years ago I had some alcohol brought back from Europe that I failed to declare. The choice was to pay the tax or have it destroyed and pay for the destruction. Either way you're gonna pay.
Having said all of that, there seem to be lots of other things like this that do make it through customs, and one gets the impression that Sparkfun would have had no problem if their bribe had been big enough.