The problem is reusable straws are more of a hazard to the animals than disposable straws, especially if they were to switch to the bio based straws that are made from food waste (i.e. corn husks and other inedible parts of plants), as those naturally degrade before causing harm to the animals while reusable straws cause harm to the animals and must surgically be removed.
Additionally, the bio based straws work for people with disabilities that need "plastic straws" when paper straws fail for many of them and they don't have the funky taste that paper straws do. These straws are also fully compostable and the same type of material can be used to make disposable silverware, plates, napkins, etc.
Even if you didn't want to use the straws, there would need to be disposable silverware, plates, etc. all of these can be made of these materials, Sea World San Diego, as well as many zoos already use them. To that end many zoos use reusable cups priced around $5 with attached reusable straws in place of disposable cups, eliminating the issue of straws potentially getting into animal enclosures and eliminating a lot of waste with paper cups, they then offer refills on the cups at around $1.
If this was truly about saving the environment, then one or more of these options would be used, this far more about profit that environmental benefit at this point.
I am all for helping the animals, but what I am not for is claiming you are doing something to help when in reality all you are doing is saving money and in the process may actually be causing more harm than good.
It is a similar issue to the plastic bag ban in California, while it sounds like a good idea, we have ended up with far more litter and people not picking up after their pets than before the ban, both of which are ending up in the ocean and right now we are seeing a massive increase in sick sea life. They won't admit that this may very well be the cause, because it wouldn't be politically correct to do so, but it might at least be a contributing factor, again all in the name of the environment while it is really giving the companies more profit.