Is it a good practice? That’s like asking if the Pope is Catholic. 
All kidding aside, it still blows my mind how much trust people put into manufacturers, especially in this 3D printer industry that’s basically the wild west, largely dominated by Chinese companies working under the Chabuduo mindset. If you haven’t heard of it, it’s this “close enough is good enough” philosophy that’s pretty common in Chinese business. Westerners see it as cutting corners or flat-out sloppy, and it really shows in the products they deliver.
To answer your question: we’ve all gotten products from China that don’t live up to Western quality expectations, and filament makers are some of the worst offenders. You’re not alone thinking, “Well, it came sealed from the factory, so it must be perfect, right?” But yeah, how’s that working out for us? Most of us have learned the hard way.
Basically, assume anything from China went through little to no quality control. Drying the filament before use is a must. If you’re OCD like me, you’ll start logging weights before and after drying and building your own “Naughty List” of brands that don’t dry their filament properly before sealing. Sadly, Bambu is right up there as one of the biggest offenders, and they’re charging a 40% premium! You’d think with those prices, they’d at least do the basics like drying the filament. But nope, we’re left picking up the slack. So yeah, if you’re using any hydroscopic filaments like PETG, make sure you dry it yourself. It’s just what we have to deal with in this industry.