Too much information…
If @Ewan thinks that the sweet spot is £8-15, and I don’t want to argue, why is this not reflected in what is available in the enomatics? Today, the free one has 8 wines, of which 5 are under £8. There is also one at £14.50 in the paying group of 8. Of the 16, therefore, only a quarter are in this range. There is little point in putting the cheapest on tasting: if I want to experiment with a wine at £6.75 (2 on the enomatic today), I’ll buy a bottle.
Possibly one answer is that sales in the sweet spot are strong enough and what they want to do is expand the sweet spot?
Looking at the whites in particular it also looks like the selection is very seasonally orientated. If ever you’re going to drink vinho verde for instance, surely this is the time and weather for it.