Dota 2 and other betas

Because Dota 2 actually is hard to get whereas the others are handed out to everyone who can tie their own shoes.

Because Dota 2 and CS:GO are very rare. If we were to allow Nexuiz you would get flooded with them.
Also you can get Nexuiz for free so it wouldn't make sense to spend points on them and SMNC has been released, you don't need an invite.

also, SMNC is in open beta now

Cause of mods.
It's not your site and not mine. Ask in support.

Only closed betas are allowed as giveaways. Things that are free to everyone are generally not allowed because, well, they're free to everyone. If allowed, there would be so many such giveaways that it would be troublesome for anyone not using the plugin filter to find other giveaways. Experience has demonstrated this and necessitates the policy.

OK, it's clear why some betas are allowed and some are not.

Now is there any explanation on how the point value of the allowed beta giveaways is established?

I mean, some of those free betas point almost as much as some super fashionable and expensive "thanks for" games. /just-asking-not-polemic-mode=on

dota 2 is certainly not rare anymore lol. going by the rarity logic dota 2 should be forbidden. ive had 6 copies pass through my hands in the past day and a half, and they only cost me ign keys.