First, there is the issue that here in Brazil previously we had a government monopoly on telephony, and the breakup was made along geographic lines, those are not strictly enforced anymore, but carriers sometimes still don't work at all in certain states, while other carriers work in those states (And don't work in other states), thus people that travel a lot have no choice but to own multiple lines.
Also, carriers here tend to have wildly different packages, that are advantageous in different situations.
And yes, sometimes people DO put several phones on their cards, usually whoever deals directly with sales (ie: salesmen, marketing, or CEO of small companies)
First, there is the issue that here in Brazil previously we had a government monopoly on telephony, and the breakup was made along geographic lines, those are not strictly enforced anymore, but carriers sometimes still don't work at all in certain states, while other carriers work in those states (And don't work in other states), thus people that travel a lot have no choice but to own multiple lines.
Also, carriers here tend to have wildly different packages, that are advantageous in different situations.
And yes, sometimes people DO put several phones on their cards, usually whoever deals directly with sales (ie: salesmen, marketing, or CEO of small companies)