I assume that Huawei are referring to selling their Google free Android phones in the West rather than at home in China.
Most missing Gapps could be dealt with by having shortcuts to the web versions for stuff like Youtube, Gmail, etc on the phone which might be enough for most people. But even if they put on an alternative app store its going to look quite bare compared to the Playstore. And some apps rely on Google Play services to function so would need to be re-coded to work without it.
Even Amazon who have had a lot longer to build an alternative Android compatible app store, have struggled to get a lot of app developer to create versions of their apps to work on FireOS.