I buy a replica shirt or polo shirt if I like the design & the colour(s).
In some years I've bought the home shirt, in others I've bought the away shirt & occasionally bought both with the odd testimonial shirt thrown in if I like the player & the shirt.
In other years I've not bought any.
It's a (relatively) free world & I exercise choice.
But I do look forward to the kit launches just to see what they look like.
I don't care what anybody else does, that's up to them.