Yes. I have 4 Eneloop wall chargers that always stay plugged in. (8aa and 8aaa are in them on stand-by).
And my Olight Omni-Dok charger and Tenergy 4 x C/D chargers are always plugged in.
I unplug my charger when not in use
Joshk, thanks for the pic of the SP1 with the kill-a-watt!
Well we all know errors have the greatest impact on tiny measurements like the vampire current I was measuring. But it’s an incredible device for $17. Let me say that again, $17. Here is how it compares to a fully calibrated $500 Fluke 87v with True RMS.
Fluke 87V True RMS Multimeter with AcuCal calibration
123.0 V
0.016 A
60.01 Hz
Kill-A-Watt P3 P4400
123.4 V
0.01 A
60.0 Hz
0.28 PF
2.1 VA
That goes beyond the accuracy I would expect for $17 and makes this an incredible device. ToyKeeper can back this up I bet, but it’s very likely the Amps are truncated for display instead of rounded so they could be much more accurate than this test reveals.
I won’t be tempting fate for more tests.
perhaps HKJ would be interested in testing this?
No, it is a device for measuring US mains, it would not get a fair test on EU mains.
That sucks 
I’m guessing they don’t make an EU version?
I’m just not setup to do it safely. And I’m unsure how many readers are on this thread. And even if I test the crap out of mine the next point someone will make will be that it’s only the results from one Kill-a-watt. And it’s a good point. Even if mine is incredible, we don’t know if the next one sold is the same. Although with my luck I’d say I didn’t get the only good one. 
I have not seen a EU version.
The main problem is the different frequency (I can handle the voltage). With cheap measuring equipment the difference between 50/60Hz might not be handled very well, that might give errors you will not see when using it in US.
The two professional watt meters I have handles it without problems and they do also handle power levels below 1watt with good precision and resolution.