So-called "LoCall" numbers: more expensive

I notice from my mobile bill that so-called "LoCall" numbers actually cost me extra money. I'm already paying for a set number of national calls per month and I never use all these minute up. But when I ring a "lo-call" number it is not included in these minutes and therefore I am paying additional.

I checked the Revenue website looking for a non-"LoCall" number for PAYE workers to ring but it doesn't have any. My last 1890 333 425 call to Revenue cost me €1.61 extra, even though I have hundreds of national minutes left on my bill. Years ago you could just ring an ordinary number and get through to Revenue.

Aside from the irony of a so-called LoCall number costing much more than an ordinary number would, what benefit does the Revenue have in not allowing us to ring a standard phone number?