I remember saying 发票 most of the time.
Agreed: living in Beijing, at least, 发票 is what all the taxi drivers & shops say.
小票 (xiao piao) is more commonly used than 收据 in casual conversations.
收據 ok,發票 is more commonly uesd in Taiwan.
收 (shōu) = to receive/to accept
据 (jù) = according to/evidence/proof
收据 (shōujù) = receipt
We learned 据 before in:
根 (gēn) = root/basis
据 (jù) = according to/to depend on
根据 (gēnjù) = according to/based on