I certainly agree that many consumer electronics items stand up very well in a "marine environment". As Chuckles points out, for non-safety items you can get away with items which are a lot less expensive than their "marine" counterparts. Some things are ridiculously cheap...almost throwaway.
That said, to paraphrase a famous ex-President, "it depends on what the definition of [a marine environment] is".
The Chesapeake Bay IMHO is not a marine environment in the same sense as, say, the Caribbean or even South Florida are. First, the Bay isn't very salty. It's fed by numerous fresh water tributaries and is only brackish. No where near the salt density as many ocean environments, even those 50 miles to the East on the Atlantic Coast. Next, it isn't hot and humid all year round. There are terribly hot days during the summer, of course, but not 365 days a year.
My boat was in the Eastern Caribbean for 11 years, and has been in the Chesapeake area for most of six years, when it wasn't in Maine or Florida. I've noticed a difference in the maintenance requirements here vs. warmer and saltier climes.
I've also lived in tropical climates and have maintained electronic equipment there (in SE Asia, South Asia, and Africa). IMHO, if you take care of your equipment....keep it clean, covered when possible, and out of the tropical salt air....it will last a very long time even in those hostile environments.