Those QR bikes may have forward facing dropouts. It lowers the likelihood that the wheel will be ejected. I have an All City disc brake bike that I bought after TA showed up, and it still has rearward facing dropouts. But I have never had an issue with the wheel coming out. The funny thing about QR and disc being mostly available on low-end bikes is that most low-end bikes are sold to people that don't know how to use a QR and don't know that they should learn about it.