Some campaign allows new account, but most do not allow for the simple reason because of cheating. It is an easy way to register the new account just for the campaign and get earning or bounty.
If you think for a new Twitter account, Usually they do not mean anything with couple followers. No one wants to pay for futile promotion.
Nowadays, most of the altcoin coin campaign are getting into scams without paying to the participants. Really each and every participant should understand those altcoin owners should recruit a campaign manager for safety reasons.
I am a little distrustful about new altcoin ICO campaign. Especially in recent times, there have been several scam coin.
I don't know much about altcoin twitter campaigns, so if you have experience with them, maybe write few words in OP about them.. I mean what is important when we want choose one.
Do they use escrow, how we can check value of altcoin or something what in your opinion can be important.
I linked every campaign with campaign thread, and there you can find all details information about the campaign. Every campaign has different rules, and many of them do not have a specific campaign manager and have no clear rules. There are too much jobs for me, and it is more material for a blog(i am thinking about this)
You choose campaign for which you consider that a good and you expect to receive payments. I refuse to add those who I appear to be little risk or cost-effective