At my place of work they have a WMF Bistro (see picture below for the actual machine). It's an automatic.
I notice that the espresso is not that good. It's more like 'normal' coffee, but only stronger and in a less amount. Very little crema and bitter.
The milk on the cappu is bad.....very bad. Just a little foam with lots of air in it....

My question is: how does this kind off commercial machine compare to (let's say) an Bezzera BZ07 and a Vario? And how is the quality of the grinder in a machine like the bistro?

Is it normal to have such a difference in quality with my home-setup?

The machines for home that you suggested, if fed excellent fresh coffee, will be head and shoulders above what you are getting from that Superauto. I feel bad for that machine, as it is likely being fed stale coffee, and doesn't stand a chance.

What will the grinder be like in such a machine? Flat burrs I think?

Does it compare to the quality of a Baratza Vario.....tastewise I quess not!

And indeed I use fresh coffee not older then a week from roastdate most of the times.

The Vario will be at least the equal to and probably a much better grinder than the superauto has. Superauto machines are built for convenience and inevitably produce mediocre drinks.. which a surprisingly large number of people still enjoy. With practice, you can make much better shots with a Vario & Bezzera.

And why is it that no automatic milkfoamer (like in this superauto) can produce good microfoamed milk? Not even close. You really can not compare it to good 'handmade' microfoam on a semi-automatic.

Don't know about commercial superautos, but most consumer models have thermoblocks and these generally aren't capable of producing great brew/steam pressure or temperature as well as usually having fairly wet steam.

This model just produces 'automatic foamed' milk.....just pours out of the spout. Just lots of air and bubbles.

Because that was the best easily engineered. And if their sales numbers remain good, there is little incentive to change/improve. Superautos have a different market demographic than semi-auto/automatic machines.

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