087-0 numbers: are they training staff?

I’m interested to know if there’s a new trend in companies using disguised premium rate 0870 numbers (see the saynoto0870 guide). Twice in the last week I’ve been given 0870 numbers to dial, yet rather than being told the number is 0870-123-123, both times it’s been told to me as 087-012-3123. Thus the call operator is never actually saying the phrase 0870. Cunning devils…