But for example they can never force a supermarket that accepts bitcoin to ask for KYC when someone pays for a bag of chips.
?
Precisely this draft aims to do just that. o_e_l_e_o has explained it well, and you gave him merits for that.
Well, it depends on how the merchant is set up, as I explained here:
If a merchant accepts bitcoin directly then (at least for the time being) they can avoid this, but if they use a payment processor then they will be collecting KYC as well as information on the source of your funds for all transactions.
If a merchant is directly accepting bitcoin in exchange for goods or services, then they are simply a merchant who accepts bitcoin, and are not a "crypto-asset service provider". If a merchant, however, uses a payment processor to accept bitcoin in exchange for goods or services, then the payment processor is a "crypto-asset service provider", providing services on behalf of the merchant, and are therefore obligated to collect KYC and information about the coins you are spending.
That's my understanding, at least, but not being from the EU I am hardly an expert on EU law, and if EU politicians are anything like US politicians, they will openly twist and interpret the wording to mean whatever they want it to mean.