Well, actually no, they don't want to stay home. Some chemo cycles can last a year.
People in this situation dont and should not have to sit at home for a year. A couple of well timed gummies can get you over the nasty peak post treatment and at least maybe let you enjoy a week on beach somewhere in the sun before you have to go back and start the next round of hell.
The 300lb sloth next to me, drinking vodka tonics and taking up half my seat on the airplane is probably taking a dozen different nasty synthetic pills to live through the same vacation trip as a chemo patient who might have a few edibles in their pocket. The stark differences being that some guy in a suit is making way more money off those pills, and they won't land you in a foreign prison.