From my tax knowledge, in South Africa it's difficult to get away with paying ridiculously low amounts of tax consistently. The corporate tax rate is 28% taxed on worldwide earnings. Though you prepare returns as a single entity (i.e. each subsidiary files its returns and the holding company would also file its own return), there are transfer pricing provisions, as well as provisions for connected persons (related parties/companies) that make it difficult to just keep 'profits' in Ireland without paying taxes on them.
If I could argue that if FB was headquartered in SA it would be paying at least 20% effective taxes, then surely the issue would be that the specific countries (US and EU) have lenient tax laws. Companies will keep gaming the system if lawmakers don't have the appetite to ignore company lobbying and do what's best for the income of their countries.
Whether the issue is that they don't want to lose the business of these tech companies is something else.
South Africa started imposing VAT on digital services sold by foreign companies last year. As a result my Google Play Music subs started costing me 14% more, funny enough as I technically shouldn't even be having All Access as I'm in an 'unsupported country'. Apple still charges me the same for music, which means someone had to take the loss to keep the value the same. Nonetheless, some people are unhappy, but our country gets to benefit with the extra 14% collected.