i just stay away from beaches....fine sand is such a pain in the keester that Im very leary of being near it wtih my bike.
and ya, lubing often and good wiping with rags is all Ive ever done, and my drivetrains last a good long time. In warm weather, I use stuff like Phils Tenacious, and when in fall when colder and closer to freezing, I like using the thin ones -triflow type stuff, also if Im in really dusty conditions, less "****ering" that sand and stuff sticks too (but the thin ones to me require putting on more often, but are cleaner, and fast to go on and wipe down)
If in rain often, Phils stuff stays on better and less chance of rust forming imo.