I do
In Mexico the straws are brown paper after three sips they collapse.
Ever try to drink a thick drink out of a paper straw?
In other places we have found the straws to be the very thin kind that are
used in bars as more of a stirrer than a straw.
Trying to drink something thick like all the frozen drinks through them is a
real drag.

I always bring a giant thermal cup and a pack of straws.
I fill my cup before we head to the beach or turn in for the night, I find I
am always thirsty in warmer climates and having a cold drink with me helps.
Of course if you don't bring a cup you can always buy a soda in the gift
shop.

OK...... good advice

But in an all inclusive aren't all drinks provided
free?

Why would I need to buy anything in a gift shop?