Some friends are going on vacation and I have no doubt, that given their track record at home, they need to take a first aid kit on vacation with them. Another set of friends laughed at me a few years ago when I brought them a gift as they were ready to leave... a first aid kit. Turns out I was right and they thought of me more than once over the course of their vacation. That same year I made first aid kits as Christmas gifts... one for everyone who had a car, in colors that matched their car. Everyone of those first aid kits is in a car and has been used more than once. I added belt loops to the back of a toiletry pouch with a zipper and a first aid embroidery design and then added the basics.
Everyone does different things on their vacation but odds are it's not things you are used to doing and someone is going to get hurt... hopefully hurt only in as far as they will need some quick first aid and not a trip to a local emergency room. Being prepared is the best way to keep injuries under control without having to make a mad dash to find a pharmacy in a hurry.