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[Torchwatch]

If you find yourself in the situation where no speedos are visible on a beach you may choose to conform and wear big baggy long boardies, you may rebel and wear speedos but be made to feel highly uncomfortable, or you could wear shorts a bit shorter and neater than the others and set an example they can follow. Whatever length of shorts the majority choose, select something maybe 4" shorter. Those who remember the freedom of shorter shorts will follow your example while many younger guys brought up with board shorts will be inspired and follow your example.
Be prepared for the day when the majority are wearing shorts the same length as yours and have a pair of shorts 4" sorter than that at the ready.

The main beach alongside a town with adjacent parking will tend to attract people conforming to the current fashion. Perhaps you need to go to a quieter beach outside town that requires a bit of walking to reach. With fewer people there maybe you will be able to wear your speedos in peace.