The actual reported cases of B6 toxicity are very few...it is very rare in fact. This goes back to days when PMS treatments used 500mg a day and that ended up with a few toxicity reports.

People are all over the net with supposedly high B6 readings.
Not many but it is fairly easy to find them if you Google it.

The ranges for vitamins were prepared using people considered to be "normal" and not taking ANY vitamins. Any intake will result in a different reading from the old ranges. The ranges therefore do not pertain accurately to anyone consuming B6 in foods or supplements.
Many foods today are fortified, and energy drinks, like 5 hr energy, etc contain B6. Almost all breakfast cereals and nutritional bars contain B6 now.

Also one cannot rule out lab errors. Vit D3 had two episodes of errors due to poor calibration at Quest diagnostics over the years. Labs do make mistakes, and since B6 is not commonly tested, the equipment or tech may have not kept the system up to date, or the test sample may be corroded. All vitamins are tested in labs using "known samples"... so since they are not stable in solution, they can degrade over time, especially with tests done infrequently like B6. Equipment calibrated to degraded samples which are low, will then show a factitious elevation.

Here is my B6 thread on NT:

http://neurotalk.psychcentral.com/thread30724.html

Pyridoxine B6 in most vitamins is inactive... it must be converted in the liver to P5P. If this fails the pyridoxine may build up in the serum. That might provide a false elevation.

Look at all the foods you eat and see what is on the labels. You might find you are eating more than you realize.