in my case, I know what's there when I get there, vs what I can bring. I tend to stay outside of Lahaina on Maui, and there's a CVS pharmacy (long's drugs), a

in my case, I know what's there when I get there, vs what I can bring. I tend to stay outside of Lahaina on Maui, and there's a CVS pharmacy (long's drugs), a Walgreens, and a Safeway. all of them tend to carry the same mass-market greasy sunscreen with low spf values. my skin does not do well with that, and I end up extremely sunburnt. bringing my own ends up being a better value proposition. editing to add: if I'm on vacation, I'm checking a bag, so taking extra liquids is no problem. if I'm traveling for work, I have a bag already packed with everything within TSA requirements, so no need to try to track down a store to walk or ride to somewhere near my hotel.