my understanding is that squareup.com sucks and keeps your money for a long time which is why they can offer lower rates because they are holding onto your money and making money
From what I've read, they hold anything over $1k for up to 30 days. Their rate isn't that low - 2.75%
It seems too be steered toward low use situations. If you need to do more than $1k, there's better options.