There are pro points every way. If these needed barb fittings on the outside too (feed because overflow is not an issue either way) they would have designed it so. Yes, people need to understand the importance of a square cut tube, I’ve seen side cutters used to create a nice angled cut and the guy moan the Festo leaked!
i don’t think I have ever seen a CM tank in a CARF model here in the U.K.-but guys realise the smooth outer finish is way less important than the smooth inside surfaces CARF mould. The clunk running over the rough cloth must wear debris over time…