I started fishing in the mid 1950's when i was ten years old. I lived near the Rickenbacker Causeway.
Here are some of the habits/rules of yesteryear:
In the winter old timers fished for Spanish Mackerel with equipment they must have brought down to Fla from surf fishing in the NE. They cast'ed their conventional reels spooled with Dacron line way out from the bridge. They fished on the bottom with a bank or pyramid sinker and live bait. Their rods that were usually over nine or ten feet long They caught huge numbers of mackerel in this fashion. They spaced out a half dozen rods or more and hogged the entire bridge until a group of young teenagers challenged them for space and fights broke out. These old timer bullies usually lost these fights, since they were outnumbered three or four to one. Then Dade County passed a regulation on Rickenbacker limiting the rods you could actively fish with to just two.... in an attempt to stop the chaos.
In the early 1960's, bait and tackle stores did not sell chum as far as my memory goes. I can remember reading about a tip in a fishing magazine that suggested buying a few cans of tuna or cat food. Then the article said to punch holes into one of the cans and attach it to your fishing line.
Nobody ever iced down their catch but just placed large numbers of mackerel or anything else they caught in galvanized buckets of seawater. Portable coolers were made of galvanized steel and were heavy, so i never saw them in use on any bridge or shoreline. My family owned a steel Coleman cooler but i don't remember ever filling it with ice, since the only ice i had access to, were two small trays in my family's small refrigerator freezer that only made one dozen ice cubes per tray. I remember ice was only available in large 25 lb blocks and were not commonly sold in bait & tackle stores or grocery stores. The first large portable coolers i saw were make of Styrofoam.
I never saw a trailed boat over 20 feet until around the mid 1960's and then they were not more then 24 ft in length and were not very common.
You could rent a small 14 ft. boat at various marinas for very little money if you brought along your own small outboard engine and fuel tank. If you broke down the only signaling device you carried was a white towel that you waved over your head at a passing boat. You also carried a lot of water. If you ventured offshore you might just see one or two boats all day long.
The only bag limit on fish that i can remember were for snook (Four per person). It seems no other saltwater fish had a bag limit, but a few had size limits.
In early 1970's, the Everglades National Park had a rule that outlawed chum but it was not enforced. The first time i ever saw the use of large amounts of chum was when a 24 or 26 ft charter boat based in Flamingo docked and unloaded 250-300 Spanish mackerel. I then quizzed the tourists that came off the boat and they told me about the chum the captain employed. They said he used a large bag of frozen cut up fish carcasses and maybe some wet cat food.
Chum was still non existent in bait and tackle stores so i started making my own and used a net from the produce section of a grocery store. The next week i followed the same Flamingo charter boat by just taking a compass bearing on his route out into Florida Bay. After twenty miles I finally spotted him on the horizon and anchored about 150 yd's away. When he saw me anchor he moved about a mile away from me, but i stayed put. About an hour after i employed my home made bag of frozen chum the water turned dark with mackerel and i got cut off just about every time i hooked up. I didn't know to move to the edge of this mass of fish and soon ran completely out of hooks and lures. I only boated about 8 fish by snatching them as soon as a fish grabbed a bait that I dangled a few inches from my rod tip. Soon an experienced angler showed up and anchored up about 100 yards from me on the edge of this mass of fish. He later told me at the ramp he landed over 100 mackerel on spoons that were attracted to my chum.