Which issue? That people don't check the transaction fee when signing the transaction?
Not really it's more like people that agree on a payment in BTC and who are then coming back complaining about the fee and asking if it's possible to use a different payment provider to pay for their purchase.
Now i believe these individuals are sometimes trying to do a payment from an exchange or from some sort of trading platform but it is a persistent problem, it is by no means an isolated case this happens quite a lot and that tells me that there is a problem now you can of course blatantly point to the people but i can assure you that there is an issue with the technology that they are using and that it needs to be solved if Bitcoin ever want's to reach it's full potential.
It could of course be possible that they are using the wrong service with the highest spreads, because the service providers also want a piece of the cake, but that just shows that there is a lack of a standard and as you know standardized things flourish because they are widely compatible. Bitcoin in it's current state is more like a jungle full of screaming wild animals.