In general, if an idea/niche is profitable, you will have competition. In fact, if you have idea and there seems to be no competition, that should itself be a red flag.
Fortunately, virtually no markets are truly "winner take all." And having a lower threshold for how much revenue is "enough" makes it such that you can justify attacking niches that are simply too small for a company with a huge valuation that needs to show growth multiples.
I'm assuming the situation worked out to where she had access to a shower/space to change that didn't add significant time? That feels pretty dependent on the company, office locale, and availability of amenities.
Fortunately, virtually no markets are truly "winner take all." And having a lower threshold for how much revenue is "enough" makes it such that you can justify attacking niches that are simply too small for a company with a huge valuation that needs to show growth multiples.