It was the complete opposite for me -- I only found out about Neopets [i]because[/i] of play-by-post role-play.

Shortly after getting access to the internet, I joined my first play-by-post role-playing forum, and literally on the first night in the C-box someone mistook my username for being a reference to the Neopet 'Shoryu' (which I know nothing about and only know exists because this happened), despite my username actually having no connection to it whatsoever. A few other people've made that mistake since then too, and I keep having to correct people. It's funny when people jump to conclusions.