I'm flying Porter for the first time next week and and have been completely confused by their (apparently BS) checked-baggage policy. I'm hoping someone can clarify for me.

1. If you fly alone, you get one checked-bag (up to 50lb) for free (just like Air Canada, if flying between US/CAN)?
2. If you fly with someone else on your reservation, you each get one checked-bag for free, however the combined weight must not be more than 50lb (aka you now only get 25lb per person)?!?
3. If you're flying as a family of 5 (hypothetically) you get five free checked-bags, but only 50lb combined weight (meaning each checked-bag could weigh no more than 10lb)?
4. To make this policy even more awful, they charge (and astonishing) $5 per kg over the combined 50lb/23kg???

How does this make sense??? I am truly hoping I'm reading this incorrectly because I'm immediately thinking two things:
a) This airline seems to nickel-and-dime their customers more than any US/CAN airline (and that's saying something!)
b) After being screwed out of $, (or if you knew of this awful policy) why on earth wouldn't you just book reservations for each person separately (so each person got 50lb as a checked bag, just like every other airline)???