One other reason to be loyal: you need to make a deck for the other clan too unless your playgroup is okay with you borrowing their deck for that clan.
Making multiple decks for one clan is hard enough. Especially when they share the same cards as you'll need to keep changing sleeves when you decide to play the other deck ubless all your decks have the same sleeves.
Might be doable if you bought 3 cores for yourself but not if you split with someone else.
Things might be different once we have enough clan cards not to need to splash but the neutrals will still be a problem.
Edited by muzouka