Wether they get a tender morsel of flesh to chew on, what matters is indeed the attractive 'scent' to the 'possibility' of something to eat. It's a natural behaviour for Sharks.
Now if there is plenty of 'consistent' scent along a beach, then - they will search for the 'meat'. Just ask 'Bruce' what 'scent' can do for a Shark.

There are 'many' reasons why a Shark can attack humans.
Making the local beach 'smell enticing' though - doesn't help the cause.
Why was one South African Surfer attacked by GWS's at least 5 times, with one time caught on video of two Great Whites hitting his board at the same time... while other Surfer's were not, even though 'with him'?
...his answer was because he drank a lot of beer and always pissed in the water/his wettie.
So one must guess that he smells better than the others, smells more 'animal' than the other boards.
I suggest you try an experiment FD and go spearfishing in a very chummed up area and see what sharks do appear and how they behave around you, even if you have no fish on the end of your spear. Come back and give us your results.