I don't think people appreciate enough just how cost efficient tier 1 and tier 2 runes are. Tier 2 runes are 80% as effective as tier 3 runes but a mark/seal/glyph will only cost 35 IP. It's easy to compete in ranked with tier 2 runes (although tier 3 will of course always be better) because those 2 armor, 3 mr, 3/4 ad etc. are pretty much irrelevant. So f2p players who want to spend most of their IP on champions have a good alternative. F2p players who want to do as well as they can in ranked can still buy some general use rune pages and buy fewer champs instead.
Riot also has to earn some money and people wanting to be a perfectionist with runes is one of the ways they do it. It's their right.
To the point of masteries, until level 30 you're just learning the game anyways. Unlocking masteries as you go along makes it somewhat interesting. I don't see what the problem is.