And indeed for all conventionally fueled vehicles, as well.You are looking at the predicted range, which will vary due to all sorts of reasons such as temperature, and the way you drove last time. This is completely normal for electric vehicles.
There are two separate issues being discussed in this thread. The first is that the van will only charge at 3.6kW on single phase. This is a known issue, VW have got this wrong before with other vehicles. It was advertised incorrectly in the UK, and if you don't like it, reject the vehicle. You have every right to do so, you have been mis-sold.
The second is range. The key thing to understand here is that you don't charge up in miles - you put energy into the battery, measured in kWh. The range shown is an estimate based on that energy capacity and the vehicle's consumption. The low ranges indicated are a result of high consumption. To confirm this, look at your average consumption in kWh/100 miles, or whatever your favoured units are, and calculate the energy required to go for the distance indicated by the vehicle's GOM at full charge. It will be approximately the stated useable battery capacity. If it's way less, you have a battery fault. But in 99.9% of cases, it won't be. It's consumption due to driving style, load, heater use etc. Sorry, but that's the way it is.
Hope this helps!