From the cashu.space FAQ

Mints are Lightning node runners that have decided to let you use their Lightning infrastructure to offer you a service. They will act as a custodian for your satoshis on the Lightning network, while they issue ecash to you, the user. You can think of it as in free banking, where the bank issues their own bank notes that is backed by gold. 

 Ya. Not for me at all, thanks. 

 Also I don't want anyone to be my custodian of my Sats.