Most things engineers make are useful. Note I’m talking about traditional hardware engineering, not software engineering of things like Tinder.
By that standard, I could say hammers aren't useful because I personally don't have a use for them, or payday loans aren't useful because I'm personally opposed to them.
P.s. If you don't need shelter or something to eat then yes a hammer will be of no interest to you. Likely, you've found your sugar daddy / mama on Tinder ;)