Comment by arghwhat
I can't speak for where you live of course, but they park in pedestrian areas where I live.
It's the norm in many businesses for employees to drive their work vehicle home and park it where they live, so they're everywhere. Not as many as regular passenger cars of course, but you'll see them on any residential road. Gardeners, plumbers, electricians, delivery services, this is the norm for all of them (a perk of sorts). Even big name-brand logistics companies, as it's common for the drivers to be independent contractors owning the van themselves so home is the only place to park.
They are also used for errands. They're legal for private use proportionate to the amount of VAT paid irrespective of registration type here, so you'll see them pick up/drop off kids, do groceries, recycle bottles, etc. in such vehicles too. Pretty sure that would be just as legal where you are given familiar EU rules.