Old Post and you probably have worked it out... but for others.
DRP - You receive shares "in lieu" of cash but the TAX treatment is the same as cash initially. Also later you would have a CGT event when you sell them.
BOP - You receive shares as if you bought them on the same day as your original shares (With its CGT implications ie pre/post 1985) but you loose any Franking credits and it does not count as income.
When the BOPs were first issued some people had pre 1985 shares (ie no CGT) so , a benefit.
For post 1985 acquired shares the DRP was probably better for most because CGT was worked out using CPI increases.. ie very small.
But then we got CGT discount on gains. Which mean that the BOPs in the long term are probably better off all things considered.
You mention the cost base ""full CGT (from a $0) base"" . Thats not right. The BOP shares are conceptually thought of being acquired on the same day AND price as your original shares and their numbers has to be added to the Cost Base calculation. ie their cost now becomes part of the "original cost".
1000 shares @ $1 = $1000. ten years later you have 500 BOP shares and sell the lot.
$1000 cost base/1500 = 66.66c reduced cost base. then you will pay extra CGT on the 33.33cents difference ON TOP OF whatever profit you did make ...... and thats how the ATO tries to get their money back.
https://www.ato.gov.au/General/Capi...?anchor=No_amount_assessed#No_amount_assessed
to answer your question,, Yes , why wouldn't everyone do it.. Unless you need the cash.