Your request to be payed in btc was so random. I would understand if you already know your client as a btc user, but straight up ask him to pay you in btc is kind of really odd. I think its best if you asked him first if he uses btc as payment, nothing to be surprised honestly, it is known that btc isn't used as well as fiat, we have to accept not all are using btc. Some may heard about it a few times but don't expect its so widely used. Maybe one of your client knows about it but not really use it.  And would you want your client learn btc just to pay you? Some client wouldn't go that far just to pay someone. Client will still choose the efficient way for them.