I worked over 3 years straight of full time dive resort instructor, mostly intro divers. That means at least 5 hours per week in the pool, not counting OW classes. My gear did not fade that much.
I bought that BC used off eBay for $125 shipped (10/05). The L on the shoulder makes me think it was previously a rental BC.

The picture above is from 10/07, after I'd made over 500 pool dives and nearly 2,000 ocean dives.
10 months later, diving nearly as often the whole time, I will admit the straps are faded brown. :shocked2:
It is still an acceptable blue today, but I am always on the lookout for it's replacement.

Probably like a lot of warm water places, many Maui
boat instructors who
never dive pools, go through gear faster than many
shore instructors. It's all about treatment of gear. I love the current boat I work and one reason is the good gear rinse system. Unfortunately, on most of Maui's boats the gear does a lot of sitting in the
sun even if it is washed well. :depressed:
In a resort situation you are going in the ocean right after the pool normally. Then when you get out of the ocean, everything get's a serious fresh water rinse; rental reg's should get sanitized before the rinse. The good shops I have worked for had
shaded gear drying and
weather tight storage areas. Most have had both a
wash tub and
rinse tub. I often
soak my gear for hours, some days off at home and some days at work,
including reg's. An SB search on that last topic is pretty good reading!
Disclaimers; only my first dive employer had a retail store. My current employer sells gear but has no store. I have never even been suggested to use or buy the same gear as students wear, but most of the student BC's I have and do work with were/are SeaQuest/Aqua Lung vests. :cool2: