The answer was that the main developer team already experimented with the pay-with-pink idea but pay-with-pink got thrown to the backburner for 2 reasons:
- the fiat conversion seems to be a challenge
- vendors are required who actively participate in pay-with-pink.

Basically, pay-with-pink means that the customer pays with Pinkcoin to make a purchase. There are two main transitions:
1. Fiat ---> Pink (customer needs Pink)
2. Pink ---> Shopping (customer uses Pink for shopping)

Interestingly, the main developers are about to complete a conversion tool (there was a screenshot on slack, it looks intuitive and easy to use) that allows to convert Pinkcoin to a multitude of cryptocoins. Let's say, if a vendor accepts Bitcoin for payment he or she already can accept payments in Pinkcoin.

For me this looks like for transition 2 (=shopping with Pink) Pinkcoin should already be in a good position once the tool for automatic conversion into BTC is fully up and running. This will allow any shop who accepts Bitcoin to accept Pinkcoin as well.