Saltwater and Rust

Both this summer and in previous years we've brought our bikes to the coast, we've noticed rust forming alarmingly quickly - even with the bicycles kept indoors. The chain is usually the first to rust, with the various bolts that hold components together shortly following suit. Even hardy powdercoated frames are not immune to this: We noticed rust spots on the Co-Habitant's pale blue Surly at the end of our first week here. I am curious how those who live next to salt water year-round take care of their bicycles. If the rate of rust formation we are seeing is any indication, it seems that bikes kept near salt water are liable to become rust buckets in no time.

On the other hand, I recall that my parents - who live around the corner from a marina - have always kept bikes in the garage, which was left open more often than not. These included my old mountain bike - which was stored in this manner for 15 years before I retrieved it, and the vintage Raleigh we later restored - which must have been kept there for over 20 years. Neither of these bikes show any more rust than is typical for their age. Could it be that bicycles were somehow rust-proofed in the past, and that this is no longer done? Or does rust formation slow down after an initially vigorous attack? Insights from coastal dwellers appreciated!